Mathematical Routines in Community Populations' Interactions

1. 1st Period Review Projects 2015

2. Chapter 2015: Review 1. What is Learning Objective 4.12? -The student is able to apply mathematical routines to quantities that describe communities composed of populations of organisms that interact in complex ways. 2. What is Science Practice 2.2? -The student can apply mathematical routines to quantities that describe natural phenomena. 3. What can LO 4.12 be used to describe? - Predator/prey relationships (Fluctuations within predator or pray result in coinciding—yet delayed—fluctuations in the other) **See Figure 4.12** - Introduction of species - Global climate change models 4. What important lessons have been learned thorough LO 4.12 - Reproduction without constraints result in the exponential growth of a population (seen in r-selected species) - A population can produce a density of individuals that exceed the system’s resource availability - As limits to growth due to density-dependent and density-independent factor are imposed, a logistic growth model generally ensues (seen in k-selected species) - Demographics data with respect to age distributions can be used to study human populations (large base=growing & young population , small base=shrinking & old population) 5. How does LO 4.12 connect to SP 2.2? - The “natural phenomena” described in SP 2.2 are the “communities composed of populations of organisms that interact in complex ways” in LO 4.12. An example of a mathematical routine would be determining the rate of change of population (dN/dt). 6. What equations model growth rate? - Exponential=rN; Logistic= rN[(k-N)/k] - r=(Births-Deaths)/N Logistic growth models represent populations with limited growth due to density-dependent and density-independent limiting factors. Which answer choice represents a density-dependent factor and a density independent factor, respectively? Predation; Natural Disaster Clear Cutting; Competition Disease; Predation Seasonal Cycles; Parasitism Hurricane; Hunting Figure 4.12 Example of Predator/Prey Relationship A certain population,A, (population=483; births=97; deaths=39) is experiencing exponential growth. (i) What is the individual growth rate (r) (per capita reproduction rate)? (ii) What is the population growth rate? Another population, B, is experiencing logistic growth (population=483; rate (r) same as determined in (a.i); carrying capacity=3864). (i) Calculate the population growth rate. (ii) Given that the growth rates were the same between the two populations, why—biologically—are the population growth rates different between the two populations?

3. Chapter 2015: Review • What was the answer to the multiple choice question? • - A • 2. What was the answer to the FRQ/Math question? • (a.i) r = (B-D)/N = (97-39)/483 = 0.12 • (a.ii) dN/dt = rN = 0.12 x 483 = 58 • (b.i) dN/dt = rN [(k-N)/k] = (0.12)(483)*[(3864-483)/3864] = 50.7 • (b.ii) Population A was experiencing exponential growth. This indicates • that the population was not affected by limiting factors such as • space, competition for food, disease, predation, pollution, or the • ability to find mates. Unlike population A, population B was • effected by these factors, causing logistic growth and a lower • population growth rate than population A. • It is possible that population A is an r-selected • species while population B is a k-selected species.

4. LO 2.24: The student is able to analyze data to identify possible patterns and relationships between a biotic or abiotic factor and a biological ecosystem (cells, organisms, populations, communities, or ecosystems). SP 5.1: The student can analyze data to identify patterns or relationships. Explanation: Biotic and abiotic interactions affect every biological system. They affect cell activities, organism activities, and the stability of populations, communities, and ecosystems. Resource availability is one factor that affects all three of these in various ways. Additional examples of how organisms are affected by interactions between biotic and abiotic factors include predator-prey relationships, temperature, and symbiotic relationships. The types of symbiotic relationships are commensalism, mutualism, and parasitism. In commensalism, one organism benefits while the other does not, but neither organism is harmed. Mutualism is when both organisms benefit. In parasitism, one organism benefits and the other is harmed. The stabilitity of populations, communities, and ecosystems can be affected by the availability of nesting materials and sites, food chains and food webs, species diversity, population density, and algal blooms. Nests are important to the stability of bird populations because nests are utilized by birds to protect eggs. Both continuity of common ancestry and change because of evolution in different environments are reflective of homeostatic mechanisms. Some homeostatic mechanisms can be found in organisms of various domains, while others have evolved in organisms. Biological processes are effected when there are disturbances to homeostasis. To counteract infections and other disturbances to homeostasis, organisms have evolved a variety of defenses such as immune responses. In ecosystems, homeostatic disturbances affect the balance of ecosystems and the interactions between specific organisms. M.C. Question: During the summer, a temperate broadleaf forest experiences a significant rainstorm. In temperate broadleaf forests, there are significant amounts of precipitation during all seasons. Which of the following best represents a direct abiotic result of the storm, and a biotic result due to biotic and abiotic interactions? • Nutrients will seep into the soil and plants will use these nutrients for respiration • Erosion will occur and the decreasing amount of soil will cause an increase in decomposers C. Nutrients will be leached from the soil which will stunt plant growth D. Weathering will occur and cause immediate habitat destruction FRQ-Style Question: All biological systems are affected by biotic and abiotic interactions. A. Provide and describe an example of how resource availability affects each of the following: -Activities in cells and organisms -Stability in size and genetic composition of a population B. Using the food web to the right, what will happen if the squirrel population ingests a poison? C. Using Figure 52.15b, hypothesize what will happen to the clutch size of song sparrows in the next fifty years.

5. ANSWER KEY—LO 2.24 M.C. Question: During the summer, a temperate broadleaf forest experiences a significant rainstorm. In temperate broadleaf forests, there are significant amounts of precipitation during all seasons. Which of the following best represents a direct abiotic result of the storm, and a biotic result due to biotic and abiotic interactions? • Nutrients will seep into the soil and plants will use these nutrients for respiration • Erosion will occur and the decreasing amount of soil will cause an increase in decomposers • Nutrients will be leached from the soil which will stunt plant growth • Weathering will occur and cause immediate habitat destruction Leaching is when substances like calcium, fertilizers, and/or pesticides are washed out of soil or waste. Plant growth will be stunted because the plants won’t be receiving as many nutrients. FRQ-Style Question: A. Provide and describe an example of how resource availability affects each of the following: -Activities in cells and organisms -Stability in size and genetic composition of a population -Resource availability can affect activities in cells and organisms. An example is responses to the formation of biofilms. Biofilms are surface-coating colonies that metabolic cooperation happens in in certain prokaryotic species. Other examples include responses to: cell density, temperature, nutrient and water availability, and sunlight -Availability of resources can affect stability in size and genetic composition of a population through birth and death rates. When there is a change in the environment, some organisms will adapt to the change and then pass their genes on to the next generation. The birth rates of adapted organisms will increase, and the death rate of organisms that haven’t adapted will also increase. B. Using the food web to the right, what will happen if the squirrel population ingests a poison? If the squirrel population ingests a poison, organisms farther up the food chain will accumulate increasingly larger toxin amounts by level through a process known as biomagnification. In this example, large toxin concentrations will result from biomagnification in foxes, owls, and hawks. C. Using Figure 52.15b, hypothesize what will happen to the clutch size of song sparrows in the next fifty years. Within the next fifty years, song sparrow clutch size will decrease until the song sparrow population reaches carrying capacity. Clutch size will continue to slightly fluctuate to maintain carrying capacity. (Used with Part B) (Used with Part C)

6. LO 2.4 The student is able to use representations to pose scientific questions about what mechanisms and structural features allow organisms to capture, store and use free energy. SP 1.4 The student can use representations and models to analyze situations or solve problems qualitatively and quantitatively SP 3.1 The student can pose scientific questions. Fig 40.7 Bioenergetics of an animal: an overview Representation Explanation of LO2.4: The ability to pose scientific questions about features that help an organism capture free energy can be represented in the figure where if examined closely, on can see that the figure represents a stripped down version of a standard heterotroph’s metabolism. A question that could be posed is, what part of the metabolic cycle is the use of free energy actually gained back to replenish the deficit created by all the heat(energy) loss? In the representation it can be seen that the cellular respiration stage, where ATP is synthesized, is where the energy return and storage happens for further use in the hydrolysis of the ATP to produce energy. Another question posed could be, Is the ATP or the carbon skeleton where the captured energy is stored? The answer formed from the representation would be the ATP is the location of energy storage because it is the reactant that fuels both cellular work, which gives off heat(energy),and biosynthesis. MC Question: Which of these question is most closely related to storage of the free energy that is captured by organisms? How does cellular respiration play into the production of ATP? How is the carbon skeleton recycled? How is a large part of energy lost in bioenergetics? How is cellular work enabled? Learning Log/FRQ Question: In the process of metabolism in a standard heterotroph, how is energy both used/lost and stored for later use in the body and how would a decrease in cellular respiration affect the use and storage of energy?

7. LO 2.4 Answer Key: MC Question: Which of these question is most closely related to storage of the free energy that is captured by organisms? How does cellular respiration play into the production of ATP? How is the carbon skeleton recycled? How is a large part of energy lost in bioenergetics? How is cellular work enabled? Learning Log/FRQ Question: In the process of metabolism in a standard heterotroph, how is energy both used/lost and stored for later use in the body and how would a decrease in cellular respiration affect the use and storage of energy? Energy is used in processes of digestion and absorption, cellular respiration, and is also lost as heat and in the elimination of waste such as urine and feces. The Cellular respiration stage is when the gained energy is stored in ATP for use in cell growth or other cellular processes by the hydrolysis of the ATP. If the organism experienced a decrease in cellular respiration over a long period of time could result in a shortage in ATP causing cell death in extreme cases. In a short period of time it could result in the use of fermentation to produce ATP to maintain the body.

8. LO 2.11: The student is able to construct models that connect the movement of molecules across membranes with membrane structure and function. SP 7.1: The student can connect phenomena and models across spatial and temporal scales. Explanation: In cell membranes the membrane establishes the barrier between the internal and external areas of the cell, and maintains homeostatic conditions within the cell. The membrane creates barriers that aid in the formation of concentration gradients, which are vital to cell function as seen in all cells with the sodium potassium pump. The cell membrane is selectively permeable according to the fluid mosaic model of the cell from the structure of the membrane which is a combination of phospholipids, cholesterol molecules, glycoproteins, glycolipids and embedded proteins. With these structures the cell can move molecules into the cell through either passive transport, transport that does not require the usage of energy, or active transport, movement that requires the input of energy. An example of passive transport is the movement of water through aquaporins in the membrane and active transport would be the sodium potassium pump found in cells to establish the concentration gradient in the cell. M.C. Question: Which of the following concerning the structure of the cell membrane is untrue? • It is selectively permeable to substances • It establishes concentration gradients through the use of proton pumps • It is freely permeable due to the composition of proteins and phospholipids • It is composed of a bilayer of phospholipids FRQ-Style Question: Suppose you have placed a cell in an environment that is rich in K+ molecules and Nitrogen. What pathway through the membrane would the Potassium use? Why? How would the Nitrogen enter the cell? Why?

9. Answer Key- LO 2.11 Which of the following concerning the structure of the cell membrane is untrue? • It is selectively permeable to substances • It establishes concentration gradients through the use of proton pumps • It is freely permeable due to the composition of proteins and phospholipids • It is composed of a bilayer of phospholipids Suppose you have placed a cell in a cell in environment that is rich in K+ molecules and nitrogen. What pathway through the membrane would the nitrogen use? Why? How would the calcium enter the cell? Why? The nitrogen molecules would use passive transport and move through the membrane rather than having to use an embedded protein on the membrane. In the membrane small nonpolar molecules like nitrogen are able to move through the membrane because the phospholipid bilayer has areas these molecules squeeze through. The potassium will enter the cell using a integral protein pump on the membrane. The cell has an established concentration gradient for potassium and sodium so the cell will have to use energy, in the form of ATP to cause the movement.

10. LO 3.6: The student can predict how a change in a specific DNA or RNA sequence can result in changes in gene expression. SP 6.4: The student can make claims and predictions about natural phenomena based on scientific theories and models. Explanation: A mutation is any change in the genetic material (DNA) of a cell. More specifically, point mutations (Figure below) are chemical changes in just one base pair of a gene. One type of point mutation is a base-pair substitution, which is the replacement of one nucleotide and its partner with another pair of nucleotides. Some substitutions are called silent mutations because they have no effect on the encoded protein. A missense mutation is when the altered codon still codes for an amino acid and thus makes sense, but not necessarily the right sense. A nonsense mutation causes translation to be prematurely terminated and almost always leads to nonfunctional proteins. Insertions and deletions are additions or losses of nucleotide pairs in a gene. A frameshift mutation (Figure below) occurs whenever the number of nucleotides inserted or deleted is not a multiple of three, having a disastrous effect on the resulting protein. Looking at a nucleotide sequence or a defective protein, you could predict the source a mutation leading to the . Alternative RNA splicing is genes that are known to give rise to two or more different polypeptides, depending on which segments are treated as exons during RNA splicing. Due to alternative splicing, the number of different protein products an organism can produce is much greater than its number of genes. M.C. Question: A mutation is a change in ________. A) DNA B) RNA C) Proteins D) All of the above Learning Log/FRQ-style Question: What roles do introns play in the cell? How can alternative RNA splicing be important in the evolution of a species?

11. ANSWER KEY– LO 3.6 M.C. Question: A mutation is a change in ________. A) DNA B) RNA C) Proteins D) All of the above Learning Log/FRQ-style Question: What roles do introns play in the cell? How can alternative RNA splicing be important in the evolution of a species? Introns play regulatory roles in the cell. At least some introns contain sequences that control gene activity in some way. Alternative RNA splicing expands the number of proteins that can be coded for by one gene, increasing an organism’s ability to produce new proteins. New genes among a population creates genetic diversity (Figure 5.5). Reproduction of the fittest will ensure the better suited phenotype will allow organisms with the phenotype to survive and reproduce.

12. LO 3.11 The student is able to evaluate evidence provided by data sets to support the claim that heritable information is passed from one generation to another generation through mitosis, or meiosis followed by fertilization. SP 5.3: The student can evaluate the evidence provided by data sets in relation to a particular scientific question. Explanation: Information given from the data sets provided will show that meiosis plays a role in passing down heritable information from generation to generation. This is because after fertilization, the two haploid cells combine to form a diploid cell that shares information from both the mother and the father. Meiosis is a reduction division that ensures that each gamete receives one complete haploid (1n) set of chromosomes by pairing homologous chromosome, with one homologue originating from the mother and the other from the father. Homologous chromatids exchange genetic material to increase genetic variation in the resultant gametes. This will allow for the different traits to be shown within the offspring. Dominant genes and traits will over power that of the recessive genes, allowing for the heritable things to be passed down from generation to generation. Multiple Choice: Referring to Figure 1, how is it possible for the offspring to receive information from both the mother and the father? The chromosomes come together in the egg and separate to receive the same type of information in each daughter cell. The chromosomes are duplicated and placed in each daughter cell. The gametes are split in half and subjected to individual cells that combine together. The different chromosomes cross over and switch ends and the cells divide to disperse the chromosome sets. FRQ-style Question: Using Figure 1.1 to refer to, how can there be genetic differences in the daughter cells produced?

13. ANSWER KEY – LO 3.11 Referring to Figure 1, how is it possible for the offspring to receive information from both the mother and the father? • The different chromosomes come together in the egg and separate to receive the same type of information in each daughter cell. • The different chromosomes are duplicated and placed in each daughter cell. • The gametes are split in half and subjected to individual cells that combine together. • The different chromosomes cross over and switch ends and the cells divide to disperse the chromosome sets. Free Response: Using Figure 1 to refer to, how can there be genetic differences in the daughter cells produced? The homologous chromosomes would undergo synapsis and come together to cross over to change the genetic information at the tips of the chromosomes. The chromosomes align in the middle and separate to make 2 separate cells. In meiosis II, these cells then align the chromosomes and allow them to separate into 2 more cells to create a total of 4 daughter cells. Since the homologous pairs went through synapsis, the information is altered on the chromosomes, so when the chromosomes align and allow the sister chromatids to separate, everything is different.

14. LO 1.23: The student is able to justify the selection of data that address questions related tor reproductive isolation and speciation.SP 4.1: The student can justify the selection of the kind of data needed to answer a particular scientific question. • Explanation: Speciation is the origin of a new species in evolution that examines how new species develop through the subdivision and subsequent divergence of gene pools. Speciation is divided between allopatric speciation and sympatric speciation. Allopatric speciation is defined by the interruption of gene flow when a population is separated into geographically isolated populations. Sympatric speciation accounts for the geographic overlaps among populations. Reproductive isolation is the presence of biological factors, or barriers, that impede members of two species from producing viable and fertile offspring. Such barriers occur either before zygote development (pre-zygotic) or after zygote development (post-zygotic).

15. Multiple Choice & Free Response M.C. Question: Which of the following scenarios describes sympatric speciation? A) Sugar gliders of Australia outwardly resemble the flying squirrels of North America, but the ability to glide through the air evolved independently among these two related species B) Rabbits feed on different varieties of plants even though they inhabit the same geographic area C) Multiple species of closely related honeycreeper birds, found on a single island, vary in beak shape and size as an adaptation for particular diets D) The fins of dolphins and the wings of bats are both composed of the same basic skeletal elements, however the forelimbs of these two organisms have been accustomed for different functions Learning Log/FRQ-style Question: Two populations of spotted skunks are found in opposite regions of North America. Though their geographic ranges overlap, the eastern spotted skunk mates in the late winter whereas the western spotted skunk typically mates during the late summer. • Identify a reproductive barrier that could provide an answer to this question, why is the mating between these two populations from the same species hindered. • Explain how the reproductive barrier you chose contributes to reproductive isolation before or after fertilization

16. ANSWER KEY – LO 1.23 M.C. Question: Which of the following scenarios describes sympatric speciation? A) Sugar gliders of Australia physically resemble the flying squirrels of North America, but the ability to maneuver through the air evolved independently in these two related species B) Rabbits feed on different varieties of plants even though they inhabit the same geographic area C) Multiple species of closely related honeycreeper birds, found on a single island, vary in beak shape and size as an adaptation for particular diets D) The fins of dolphins and the wings of bats are both composed of the same basic skeletal elements, however the forelimbs of these two organisms have been accustomed for different functions Learning Log/FRQ-style Question: Two populations of spotted skunks are found in opposite regions of North America. Though their geographic ranges overlap, the eastern spotted skunk mates in the late winter whereas the western spotted skunk typically mates during the late summer. • Temporal isolation is the reproductive barrier that impedes the mating between these two spotted skunks. Eastern spotted skunks do not mate with western spotted skunks because they breed at different times or during different seasons. • Pre-zygotic barriers prevent successful interbreeding between two species prior to fertilization. These differences in mating patterns may have evolved from genetically-based changes, thus isolating the two populations of spotted skunks from each other. This also interferes with the ability of the two spotted skunks to produce viable, fertile offspring.

17. LO 1.15: The student is able to describe specific examples of conserved core biological processes and features shared by all domains or within one domain of life, and how these shared, conserved core processes and features support the concept of common ancestry for all organisms. SP 7.2: The student can connect concepts in and across domain(s) to generalize or extrapolate in and/or across enduring understandings and/or big ideas. Explanation: RNA and DNA’s ability to carry genetic information in all organisms, similarities in the genetic code, and the use of certain metabolic pathways in all organisms are examples of conserved biological processes shared by all domains. A similarity in the genetic code is the use of the same nucleotides in ALL organisms. Examples of conserved metabolic pathways include glycolysis during cellular respiration, chemiosmotic production of ATP, and the processes of transcription and translation for protein synthesis. Proteins are necessary for nearly all cellular functions, therefore, the presence of processes to synthesize them are necessary for all organisms to survive. In addition, the cytoskeleton, certain membrane-bound organelles, linear chromosomes, and endomembrane systems are examples of conserved core features shared by all domains. The same amino acids and organic compounds, such as lipids, proteins, carbohydrates, and nucleic acids, are also found in all organisms. The existence of these shared, conserved core process and features provides evidence that there must have been some common ancestor because all organisms could not universally share the same traits without evolving from an organism that had all of them. For example, the mitochondria and chloroplasts in cells are necessary for all organisms to produce energy needed for most metabolic processes. A common ancestor that had mitochondria and/or chloroplasts would have survived and reproduced in order for other organisms to have this trait. Figure 1.1 shows how all organisms in all three domains have evolved from a common ancestor. M.C. Question: Which of the following is NOT true regarding RNA and DNA’s ability to carry genetic information in all organisms? a) The earliest organisms on Earth used RNA as their genetic material and eventually DNA replaced RNA as the major carrier of genetic material for organisms that evolved later because it is more stable. b) RNA in retroviruses and DNA in all other living organisms directly influence phenotypic expression. c) Information that codes for metabolic processes found in all organisms is found in DNA and RNA. d) RNA and DNA can be used interchangeably to store genetic information in all organisms. Learning Log/FRQ Question: Explain why the following statement is inaccurate: “Glycolysis is not present in all organisms as a result of common ancestry. It was just evolved by all organisms over time because they all needed this process for respiration.”

18. Answers LO 1.15 M.C. Question: Which of the following is NOT true regarding RNA and DNA’s ability to carry genetic information in all organisms? a) The earliest organisms on Earth used RNA as their genetic material and eventually DNA replaced RNA as the major carrier of genetic material for organisms that evolved later because it is more stable. b) RNA in retroviruses and DNA in all other living organisms directly influence phenotypic expression. c) Information that codes for metabolic processes found in all organisms is found in DNA and RNA. d) RNA and DNA can be used interchangeably to store genetic information in all organisms. Learning Log/FRQ Question: Explain why the following statement is inaccurate: “Glycolysis is not present in all organisms as a result of common ancestry. It was just evolved by all organisms over time because they all needed this process for respiration.” The statement is inaccurate because all organisms cannot evolve the same traits over time. Glycolysis is virtually identical in organisms of all three domains (Archaea, Bacteria, Eukarya). All organisms must have evolved from the same common ancestor because glycolysis is a vital process that is necessary to produce ATP in the presence of oxygen AND during the lack of it. If an organism’s cells are deprived of oxygen, the only way they can produce ATP is through glycolysis. Without glycolysis previously existing in all organisms, many would not survive to reproduce due to their inability to power metabolic processes without oxygen for the Calvin cycle or to act as the final electron acceptor for the electron transport chain. Figure 1.2 shows how glycolysis is the only process in cellular respiration that functions without oxygen.

19. LO 3.3: The student is able to describe representations and models that illustrate how genetic information is copied for transmission between generations. SP 1.2: The student can describe representations and models of natural or manmade phenomena and systems in the domain. Explanation: Genetic information is transmitted from one generation to the next through DNA and, in some cases, RNA. DNA replication is a semiconservative process where one strand of DNA serves as the template for a new complementary strand. This process requires the enzyme DNA polymerase, in addition to many others, occurs bidirectionally and differs in the production of the leading (5’ to 3’) and lagging (3’ to 5’) strands. Genetic information in retroviruses flows in reverse from RNA to DNA through the reverse transcriptase enzyme. The new DNA integrates into the host genome. Connecting the LO and the SP requires a student’s ability to understand and describe models of DNA replication and its components. M. C. Question: In the figure to the right, Which of the following enzymes assembles Okazaki fragments during DNA replication? DNA Polymerase Helicase Ligase Topoisomerase Learning Log/ Free Response Question: Contrast DNA replication in prokaryotes and eukaryotes. Why has eukaryotic DNA replication evolved to favor theses differences?

20. ANSWER KEY– LO 3.3 In the figure to the right, Which of the following enzymes assembles Okazaki fragments during DNA replication? DNA Polymerase Helicase Ligase Topoisomerase Contrast DNA replication in prokaryotes and eukaryotes. Why has eukaryotic DNA replication evolved to favor theses differences? In prokaryotes DNA replication occurs at a single origin, does not involve telomeres, and occurs in the cytosol or the prokaryotic cell’s membrane. In eukaryotic cells there are multiple origins of replication, telomeres that cap the ends of DNA strands, and the process occurs in the nucleus (as well as the mitochondria and chloroplast when they synthesize their own DNA). The differences between prokaryotic and eukaryotic DNA replication are largely related to the differences in the size and complexity of the DNA molecules and the cells of these types of organisms. In order to accommodate a much larger amount of DNA eukaryotic cells have developed four or more types of polymerases. A rapid rate of replication occurs close to continuously in prokaryotic cells while eukaryotes only undergo replication during S-phase. This development was most likely advantageous because it allowed for the growth of more complex and specialized cells.

21. LO 1.5: The student is able to connect evolutionary changes in a population over time to a change in the environment. SP 7.1: The student can connect phenomena and models across spatial and temporal scales. Explanation: The product of natural selection is the adaptation of a population of organisms to their environment. The individuals best suited for their environment will reproduce over individuals less suited for the environment, thus changing allelic frequencies for future generations, demonstrating evolution of the population in response to the environment. An example of this is as oxygen released by photosynthesizing cyanobacteria accumulated in the atmosphere approximately 2.2 billion years ago, organisms able to use this oxygen through cellular respiration had an advantage over those that couldn’t and lived to reproduce, causing species to evolve to perform cellular respiration in response to new atmospheric oxygen levels (shown in the figure below). M.C. Question: Which of the following must be true in order for a population to evolve in response to its environment? A) The population must experience genetic drift, through which the gene pool and allelic frequencies change over time B) A mutation must occur in at least one individual that gives it an advantage in survival and reproduction over other individuals C)Reproduction of organisms with genetic characteristics that enable them to better utilize environmental resources D)The population must be small, isolated, and selectively reproduce FRQ-Style Question: Fertilizer from a nearby farm runs off into a lake, lowering the dissolved oxygen levels in the lake. How might a population of catfish in this lake evolve in response to this environmental change?

22. M.C. Question: Which of the following must be true in order for a population to evolve in response to its environment? A) The population must experience genetic drift, through which the gene pool and allelic frequencies change over time B) A mutation must occur in at least one individual that gives it an advantage in survival and reproduction over other individuals C)Reproduction of organisms with genetic characteristics that enable them to better utilize environmental resources D)The population must be small, isolated, and selectively reproduce FRQ-Style Question: Fertilizer from a nearby farm runs off into a lake, lowering the dissolved oxygen levels in the lake. How might a population of catfish in this lake evolve in response to this environmental change? Individuals in this population with genes, acquired through mutations, that allow them to function with lower dissolved oxygen levels will have an advantage over those without this trait and thus will have a better chance for survival and reproduction (natural selection/reproduction of the fittest). This trait will then be passed on to the next generation and the allelic frequency of the allele resulting in this trait will increase generation to generation as long as this trait is favorable for the individuals of the population.

23. LO 3.39 The student is able to construct an explanation of how certain drugs affect signal reception and, consequently, signal transduction pathways.SP 6.2 The student can construct explanations of phenomena based on evidence produced through scientific practices. • Cell communication is essential for the survival of organisms. It allows the cells to interact with each other and the environment around them. Cell signaling has three steps: Reception, Transduction, and Response (as shown in the figure beow). In the reception step, the cell receives a signal molecule from outside the cell that binds to a receptor protein on the surface of the cell. The signal then causes a chain reaction of relay molecules to amplify a signal to the cell, this is called transduction. These steps result in an activation of a cell to respond from a signal molecule outside of the cell via signal transduction pathways that convert signals from the cell surface into a cellular response. In the immune system signal transduction pathways send the body signals to respond to allergens, that promote the release of histamine and bodily fluids (i.e. mucus). Antihistamines are used to that prevent this response by inhibiting the receptors of the immunoglobulin E antibody to receive the signal molecule. By cutting off the signal, the antibody does not receive the relay molecules that do not activate the signal transduction pathway. Multiple Choice Question When the cell has responded to a signal and the activation of cellular response has been carried out, which of the following steps does the process take next? Endoplasmic reticulum releases Ca^2+ ions through a gated calcium channel Large proteins attach to the scaffolding protein too further relay signals to the cell Signal molecules leave the receptor, the receptor reverts to an inactive form Enzyme cascades amplify the cell’s response to the signal. FRQ Explain how the ER and second messengers influence help the process of cell signaling via the signal transduction pathway.

24. Answer Key LO 3.39 FRQ Explain how the ER and second messengers help the process of cell signaling via the signal transduction pathway. • Multiple Choice Question When the cell has responded to a signal and the activation of cellular response has been carried out, which of the following steps does the process take next? • Endoplasmic reticulum releases Ca^2+ ions through a gated calcium channel • Large proteins attach to the scaffolding protein too further relay signals to the cell • Signal molecules leave the receptor, the receptor reverts to an inactive form • Enzyme cascades amplify the cell’s response to the signal. The ER and second messengers , such as Ca^2+ ions, help the process of cell signaling via the signal transduction pathway by releasing Ca^2+ ions through an IP3- gated calcium channel. A signal molecule binds to a receptor of a cell. Phospholipase cut the polar head of phospholipids that become IP3. These get released into the membrane and bind to ligand gated channels releasing calcium from the ER. This then raises the calcium levels in the cytosol and activate proteins that activate signaling pathways.

25. Connection: Organisms, in order to survive, must be able to communicate and exchange information within their body and use it to adapt to their environment. The environmental cues can be abiotic (such as temperature or photoperiod) or biotic (such as those avoiding predators, conspecifics, or food), and the alteration produces a normal, not a pathological, phenotype, that is appropriate for the environment. Internal changes include things such as hunger, thirst, and hormones, and the body is regulated through the use of homeostasis, which requires the use of ATP, taking energy. Changes in pH, temperature, and food intake all help regulate the internal state of the body. This information is transferred throughout an organism through the use of neurons and other communication techniques, mainly involving the nervous system. Organisms that are best at responding and adapting to internal or external cues will reproduce, being an important part of natural selection. Learning Objective 3.42: The student is able to describe how organisms exchange information in response to internal changes or environmental cues. Multiple Choice: If an endotherm is placed into a cold environment, what will happen to its metabolic rate and why? • It will rise because it will have to use more energy to maintain its internal body temperature. • It will rise because it will have to use more energy as it will increase the rate of respiration • It will fall because it will have to use less energy to maintain its internal body temperature. • It will fall because it will have to use more energy as it will decrease the rate of respiration. FRQ: Insulin is key in regulating blood glucose levels. Using the figure provided, explain: • how is a proper blood glucose level maintained • how does negative feedback have a role in maintaining proper blood glucose levels. • describe how diabetes affects the regulation of blood glucose Science Practice 7.1: The student can connect phenomena and models across spatial and temporal scales.

26. Answer Key MC: The correct answer is A. An endotherm is a ‘warm-blooded’ animal, therefore it uses homeostasis to maintain a certain temperature. When placed in a cold environment, it will require more energy to maintain this temperature. FRQ: a)blood glucose levels are restored to normal levels primarily through the actions of two pancreatic hormones , namely insulin and glucagon. If blood glucose levels rise (for example, during the fed or absorptive state, when a meal is digested and the nutrient molecules are being absorbed and used), the beta cells of the pancreas respond by secreting insulin. Insulin has several notable effects: it stimulates most body cells to increase their rate of glucose uptake (transport) from the blood; it increases the cellular rate of glucose utilization as an energy source; it accelerates the formation of glycogen from glucose in liver and skeletal muscle cells; and it stimulates fat synthesis (from glucose) in liver cells and adipose (fat) tissue. These effects collectively cause a decrease in blood glucose levels back to normal levels. b)Negative feedback systems are processes that sense changes in the body and activate mechanisms that reverse the changes in order to restore conditions to their normal levels. Negative feedback systems are critically important in homeostasis, the maintenance of relatively constant internal conditions. Disruptions in homeostasis lead to potentially life-threatening situations. The maintenance of relatively constant blood glucose levels is essential for the health of cells and thus the health of the entire body. c) In diabetes, the body destroys insulin molecules, causing the blood glucose levels to go unregulated.

27. LO 3.16: The student is able to explain how the inheritance patterns of many traits cannot be accounted for by Mendelian genetics.SP 6.3: The student can articulate the reasons that scientific explanations and theories arerefined or replaced. • Why are inheritance patterns often too complex to be predicted by Mendelian genetics and provide examples? (CUES: spectrum of dominance, allele, phenotype, recessive, dominant) • The shirts in the figure below best represents which non-Mendelian inheritance term? • Incomplete Dominance • Penetrance • Genetic Heterogeneity • Pleiotropy • Codominance Gregor Mendel is known as the father of Genetics because he was the first to describe the laws of inheritance of traits. However, what many people don’t know is that Mendel’s data is controversial because he left out data and he recounted to suit his hypothesis. Not only that, but there are multiple things that Mendelian genetics does not account for, such as: Incomplete Dominance (a heterozygote's phenotype is intermediate between those of two homozygotes), Codominance (a heterozygote’s phenotype is distinct from and not intermediate between those of the two homozygotes), Multiple Alleles (many variants or degrees of a phenotype occur), Polygenic Inheritance (when one characteristic is controlled by two or more genes), Lethal Alleles (the phenotypic class dies early in development), Nondisjunction (the failure of homologous chromosomes or sister chromatids to separate properly during cell division), and Sex Influenced traits (denoting an autosomal trait that is expressed differently, in either frequency or degree, in males and females). Studies have to be refined and replaced because, in the case of Mendel, maybe someone falsified data, studies can be erroneous, environmental factors may change results, new technology advances, information could come out that could effect the original study, and or the study isn’t global enough. Also, if studies were not refined and replicated, the world would not know as much as it does now about genetics because people would just be following Mendel’s original data and resulting in the world possibly never founding out why genetic disorders like Down syndrome, Male pattern baldness, Duchenne muscular dystrophy, and Fragile X syndrome occur.

28. Answer Key-LO 3.16 • A heterozygote’s phenotype is distinct from and not intermediate between those of the two homozygotes describes which term? • Incomplete Dominance • Penetrance • Genetic Heterogeneity • Pleiotropy • Codominance • Explanation: Codominance, in this case, it means you should be able to see both parent’s shirt types; thus resulting in the little girl having a checkered pattern shirt. • Why are inheritance patterns often too complex to be predicted by Mendelian genetics and provide examples? (CUES: spectrum of dominance, allele, phenotype, recessive, dominant) • Inheritance patterns are too complex to be predicted by Mendelian genetics because a single gene deviates from simple Mendelian patterns when alleles are not completely dominant or recessive, if a particular gene has more than two alleles, or if a single gene produces multiple phenotypes. The spectrum of dominance is the range that alleles can show different degrees of dominance and recessiveness in relation to each other. One example of this is codominance, where the two alleles both affect the phenotype in separate distinguishable ways. Another example of this is incomplete dominance, which is when offspring have a phenotype somewhere in between the phenotypes of the two parental varieties. This can be seen when red snapdragons are crossed with white snapdragons and all the offspring are pink flowers.

29. LO 4.20: The student is able to explain how the distribution of ecosystems changes over time by identifying large-scale events that have resulted in these changes in the past SP 6.3: The student can make claims and predictions about natural phenomena based on scientific theories and models. Explanation: Ecosystems can be impacted by geological and meteorological changes. To be more specific, geological and meteorological events impact the distribution of ecosystems. Although there are some man-made global changes, there are also global changes that are not caused by man, such as continental drift. All the continents on our planet used to be organized into one super continent called Pangaea, and later, this super continent drifted apart. Scientists came up with this resolution, because not only did the continents fit together, but those continents had fossils that would move throughout the continent as seen in figure 1.1. This was also an indicator that drifting had caused biogeographical changes or changes in the lives that are living on the continents. Now we are able look at where certain species are found and predict how those ecosystems had changed over time. The last type is how meteorological changes, such as El Niño, can actually impact ecosystems. El Niñohappens between every two to seven years and is when trade winds weaken and warm surface water moves toward South America as seen in figure 1.2. This causes droughts in the western Pacific, and increases the precipitation in southwestern North America, resulting in a change in temperature. The change in temperature caused by El Niño can impact the development of certain creatures such as the marine iguana, whose bones shrink in response to the warm weather caused by El Niño. Figure 1.1 Figure 1.2

30. M.C. Question: Which of the following statements concerning ecosystem change is true? • Wildfires contribute to permanent damage, and ecosystem lost • Ecosystems can be altered by seasonal patterns • Ecosystems cannot repair themselves overtime • An ecosystem will only thrive once it is disturbed FRQ-style essay question: Bobby and Franky got into an argument about a lesson they learned in class. They learned about Pangaea that day in AP Biology, and the question of what would life be like on Pangaea if continental drifts did not occur emerged. Bobby stated that life would relatively be the same and the population will be dispersed evenly; however, Franky disagreed by stating that life would be drastically different and that the edges or coastal regions of Pangaea would be densely populated. Who is correct and incorrect? Explain and justify.

31. Answer Key – LO 4.20 M.C. Question: Which of the following statements concerning ecosystem change is true? • Wildfires contribute to permanent damage, and ecosystem lost • Ecosystems can be altered by seasonal patterns • Ecosystems cannot repair themselves overtime • An ecosystem will only thrive once it is disturbed FRQ-style essay question: Bobby and Franky got into an argument about a lesson they learned in class. They learned about Pangaea that day in AP Biology, and the question of what would life be like on Pangaea if continental drifts did not occur emerged. Bobby stated that life would relatively be the same and the population will be dispersed evenly; however, Franky disagreed by stating that life would be drastically different and that the edges or coastal regions of Pangaea would be densely populated. Who is correct and incorrect? Explain and justify. Franky is correct and Bobby is incorrect, because there will be a decrease in biodiversity and an increase in global average temperature if we were to be living on Pangaea. This would be due to Pangaea’s massive size as a supercontinent, moisture-bearing clouds would lose most of their moisture before getting very far inland thus, living organisms located inland would receive less precipitation. Less precipitation results in the sharp decline in biodiversity, because producers and consumers require precipitation to provide nutrients to grow and function properly. With the lack of precipitation inland this would also cause the temperature to become hot and arid especially in the center of Pangaea. Due to the lack of water and life inland, the population of Pangaea would be dense along its edge or coastal regions, because living organisms like humans require water.

32. LO 1.21 The student is able to design a plan for collecting data to investigate the scientific claim that speciation and extinction have occurred throughout the Earth’s history.SP 4.2 The student can design a plan for collecting data to answer a particular scientific question.Explanation: Phylogenetic trees and cladograms can represent traits that are either derived or lost due to evolution. The student could analyze data presented by Peter and Rosemary Grant on the effects of changes in the food supply causing rapid changes in body and beak size which drives natural selection in the finches of the Galapagos Islands. The data collected over a twenty year period includes weight, body measurements, DNA, blood samples and records of seed type of each bird. Included in the data of severe drought in which the birds with stronger beaks survived and smaller beaked species became extinct. This data can be used to demonstrate speciation evolution in action in Galápagos finches by the student. The data from the loss of the species during the drought can also be used to show extinction of a species. The loss of habit and food supply lead to loss of sightings of the species or any evidence of its continued survival. Further extinctions can be proven through the use of fossils which occur when an organism dies and their remains are preserved. Determining the age of these fossils from the finches on the island can be used to show extinction and speciation. M.C. QuestionA small group of fruit flies leave the mainland on a banana peel. The larva wash up on an island and being to populate the island. A few of the flies contain rare traits for reproduction that change the mating ritual from the mainland flies. Over several generation these traits prove to be preferred and the island fly becomes reproductively isolated from the mainland flies. What type of speciation has occurred in this population?A. parapatricB. allopatricC. peripatricD. sympatricFRQ:The most famous of the extinctions over time are the dinosaurs. During the Ages of the Dinosaurs several species appeared and disappeared each with distinctions of a particular age. a. What could have caused these changes? b. On a broader spectrum, why do other species appear and disappear? c. What factors can lead to extinction of a species of organism?

33. Answer Key - LO 1.21A small group of fruit flies leave the mainland on a banana peel. The larva wash up on an island and begin to populate the island. A few of the flies contain rare traits for reproduction that change the mating ritual from the mainland flies. Over several generation these traits prove to be preferred and the island fly becomes reproductively isolated from the mainland flies. What type of speciation has occurred in this population?A. parapatric -occurs when populations are separated not by a geographical barrier, but by an extreme change in habitat. B. allopatric - occurs when a single species becomes geographically separated and each group evolves with new and distinctive traits.C. peripatric a new species is formed in isolated populations, when small groups break off from larger groupD. sympatric - a new species can evolve from a single ancestor while inhabiting the same geographic region. FRQ: The most famous of the extinctions over time are the dinosaurs. During the Ages of the Dinosaurs several species appeared and disappeared each with distinctions of a particular age. What could have caused these changes? There two mechanism for these changes the main being a response to a changing environment. The on-going process of continental drift which is responsible for earthquakes and volcanoes. the supercontinent Pangaea breaking up to form the continents we know today caused climate changes and isolation. Also changes in the atmospheric oxygen lead to extinction and speciation. The second are drastic events such as meteorite strikes and sustained volcanic eruptions. On a broader spectrum, why do other species appear and disappear? New species are the result of divergence between a population that already exists, Once the new organism have diverged to the point that they can no longer breed with one another a new species has emerged. Most species live for a short period of time and through the process of speciation the species that become extinct are the ancestors of todays species. What factors can lead to extinction of a species of organism? Some species have limited movement and if their environment becomes unsuitable such as by pollution the species will end. Global warming and human population expansion can also lead to the termination of a species. Some species cannot adapt to changes in temperature or climate and simply no longer reproduce,

34. LO 1.7: The student is able to justify data from mathematical models based on the Hardy-Weinberg equilibrium to analyze genetic drift and the effects of the selection in the evolution of specific populations. SP 2.1: The student can justify the selection of a mathematical routine to solve problems. Explanation: The student can determine if a population is evolving using the Hardy-Weinberg Theorem. The theorem describes a population in equilibrium. In order for a population to be considered in Hardy-Weinberg equilibrium, it must be large, isolated, have no net mutations, no natural selection, and mate randomly. The equations used in the Hardy-Weinberg Theorem are p+q=1 and p2+2pq+q2=1 (Figure 1.1). Genetic drift, natural selection, directional selection, and stabilizing selection. Genetic drift is when the gene pool of a small population changes due to chance. This occurs through either the bottleneck effect or the founder effect. A disaster must occur to reduce the population size or a new colony must be formed in which the allele frequencies would be altered. Natural selection occurs when organisms are better suited for survival and reproduction than others. Eventually the allele frequency would favor the traits of the organisms that are better suited for the environment. Directional selection is when natural selection favors an extreme of the variation. The allele frequency would be altered to exhibit the favored trait. Stabilizing selection occurs when natural selection favors the “normal” traits. Over time, the “normal” state becomes more common and the extremes become less frequent. MC Question:Huntington’s disease involves the progressive loss of selected nerve cells in the brain. This disease is associated with dominant alleles. In a population of 1000 individuals, only 510 do not exhibit this disease. How many individuals would you expect to be heterozygous? • 510 • 82 • 408 • 490 FRQ Question: The frequency of alleles are altered by evolution. A population of whales live in the Pacific Ocean near the equator. Their size of flippers is determined by dominant and recessive alleles. The smaller flipper is caused by a recessive allele. Which conditions will favor the whale population to remain in Hardy-Weinberg equilibrium? The frequency of the recessive allele is 0.35. What percentage of the dominant allele will be represented in the whale population? Using this information, what is the frequency of each genotype? http://www.brighthub.com/science/genetics/articles/100586.aspx

35. MC Question: Huntington’s disease involves the progressive loss of selected nerve cells in the brain. This disease is associated with dominant alleles. In a population of 1000 individuals, only 510 do not exhibit this disease. How many individuals would you expect to be heterozygous? • 510 • 82 • 408 • 490 The correct answer is C. If there are 510 individuals that show the recessive trait, then there would be 490 individuals that show the dominant trait (1000-510=490). This means that q2 would equal 0.51. You take the square root of this decimal and get 0.714 as q. p+q=1, therefore 1-q=p. 1-0.714 equals 0.286. This is the value of p. The equation p2+2pq+q2=1 is also used for Hardy-Weinberg equilibrium. p2 represents the frequency of homozygous dominant, 2pq represents the frequency of heterozygous, and q2 represents the frequency of homozygous recessive. You multiply these numbers by the total number of individuals in the population to get the number of individuals with each. For this problem, q2 equals 0.51, p2 equals 0.082, and 2pq equals 0.408. There are 510 homozygous recessive individuals, 82 homozygous dominant individuals, and 408 heterozygous individuals. FRQ Question: The frequency of alleles are altered by evolution. A population of whales live in the Pacific Ocean near the equator. Their size of flippers is determined by dominant and recessive alleles. The smaller flipper is caused by a recessive allele. Which conditions will favor the whale population to remain in Hardy-Weinberg equilibrium? The frequency of the recessive allele is 0.35. What percentage of the dominant allele will be represented in the whale population? Using this information, what is the frequency of each genotype? It is necessary for the population to be large, isolated, have no net mutations, no natural selection, and mate randomly in order to be in Hardy-Weinberg equilibrium. The frequency of the dominant allele would be 0.65 when the frequency of the recessive allele is 0.35. The frequency of AA (homozygous dominant) would be 0.4225. The frequency of Aa (heterozygous) would be 0.455. The frequency of aa (homozygous recessive) would be 0.1225. There are a total of 9 points maximum for this question. 5 points come from listing the 5 requirements for a Hardy-Weinberg population (large population, isolated population, no net mutations, no natural selection, random mating). 1 point is received from providing the correct frequency of the dominant allele (0.65). This number comes from subtracting the recessive frequency from 1 (1-0.35=0.65). The remaining 3 points come from listing the correct frequencies of each genotype (AA=0.4225, Aa=0.455, aa=0.1225). You plug the p and q values into the equation p2+2pq+q2=1 in order to find the frequencies of each genotype.

36. LO 3.10 The student is able to represent the connection between meiosis and increased genetic diversity necessary for evolution. SP 7.1 The student can connect phenomena and models across spatial and temporal scales. Explanation: In meiosis a diploid cell goes through cell division twice, but its DNA only gets replicated once. It produces four haploid daughter cells, or gametes that can combine with another gamete from the other parent and form a zygote. Recombination and independent assortment takes place in meiosis (refer to figure). Recombination is when homologous chromosomes are aligned side by side, and genes get traded along their length resulting in new recombinant DNA. Independent assortment is when the chromosomes move independent of each other to the different poles, so the gametes will have different order and combinations of gametes from each other, so this random shuffling of shuffling of genes and chromosomes increases the genetic diversity in a population. MC: There is a fictional species called Lambiohippotamusthat lives in a deserted part of India. Scientist have noticed that the species only has females, females have to court among each other to produce offspring and survive. The eggs can’t be fertilized since there aren’t any males, but they develop by themselves into females. No fertilization can occur, and the eggs develop into female lizards. Which of these statements applies the most to this species? A)The desert is the same throughout so having genetic diversity won’t be of much help to the species. B)Crossing over caused the females to mate. C) The species hasn’t evolved to reproduce asexually instead of sexually. D)Eventually the species won’t be able to reproduce anymore and it’ll go extinct. E) A & C are both correct. F) None of these apply to the species. FRQ Question: Through meiosis, the survival of the fittest began. Explain how this took place and give an example of an organismthat has changedover time due to meiosis.

37. Answer Key 3.10 There is a fictional species called Lambiohippotamus that lives in a deserted part of India. Scientist have noticed that the species only has females, females have to court among each other to produce offspring and survive. The eggs can’t be fertilized since there aren’t any males, but they develop by themselves into females. No fertilization can occur, and the eggs develop into female lizards. Which of these statements applies the most to this species? A)The desert is the same throughout so having genetic diversity won’t be of much help to the species. B)Crossing over caused the females to mate. C) The species hasn’t evolved to reproduce asexually instead of sexually. D)Eventually the species won’t be able to reproduce anymore and it’ll go extinct. E) A & C are both correct. F) None of these apply to the species. FRQ Through meiosis, the survival of the fittest began. Explain how this took place and give an example of an organism that has changed over time due to meiosis. Meiosis occursspecifically in sexuallyreproducingorganismsand accountsforthegeneticdiversitythat lead to thesurvival of thefittest. In meiosis thecells of eachparentundergocelldivisiontwo times. Thechromosomes of thecellscrossover in Prophase I, crossingovermeansthatthechromosomes are sidebyside and they swap geneticinformationamongsteachothercreatingchromosomewithmanydifferentsequences. Independentassortmentoccursin Metaphase I, thisiswhenthehomologouschromosomes line up randomly and can be split up intodifferenttgameteswithdifferentgeneticinformation. Whentwogametes produce a zygote, completelydifferentfromtheparents, throughfertilization, itmighthavecertaincharacteristicsthataid in itssurvival. Iftheorganismsurvivesitmeansthatit can reproduce and passdownthe favorable trait to thenextgenerations. Oneexample of how meiosis contributed to thesurvival of thefittestwasthe finches in theGalapagoswhereover time some finches developedsmallerbeaks to reachsmallerfoods and surviveagainstscompetitionwithbigbeaksthatwerelookingforfoodslikelargernuts.

38. LO 2.27 The student is able to connect differences in the environment with the evolution of homeostatic mechanisms. SP 7.1 The student can connect phenomena and models across spatial and temporal scales. Explanation: Homeostatic control systems show that species come from a common ancestor. For example, the circulatory systems in fish, amphibians and mammals are all similar, and bacteria, fish, and protest use osmoregulation to maintain homeostasis in their fluids. Organisms have various mechanisms for obtaining nutrients and eliminating wastes. Such as gas exchange in aquatic and terrestrial plants, digestive mechanisms in animals such as food vacuoles, gastrovascular cavities and one – way digestive systems, respiratory systems of aquatic and terrestrial animals and nitrogenous waste production and elimination in aquatic and terrestrial animals. The continuity of homeostatic mechanisms reflects common ancestry, while changes may occur in response to different environment conditions. M.C. Question: Which of the following scenarios consists of a homeostatic control system that has changed through evolution? I. As the physiological complexity of vertebrate animals increased, so did the need for more surface area to transport and exchange nutrients and oxygen in their circulatory system. Adaptations have allowed the development of large body size. II. Amphibians developed a second pumping circuit when the evolution of lungs created a major change in the pattern of the circulatory system. Blood is now pumped from the heart through the pulmonary arteries to the lungs and then is returned to the heart via pulmonary veins. III. When a person consumes alcohol, it reduces how much ADH (anti – diuretic hormone) they produce, therefore increasing how much urine is produced. IV. Mammals developed to have a 4 chambered heart due to the fact that oxygenated and deoxygenated blood does not mix. Deoxygenated blood from the body is pumped through the heart and to the lungs while oxygenated blood is returned to heart to be pumped to the rest of the body. I, II I, II, IV II, III II FRQ: Biological systems are affected by disruptions, both internally and externally, that alter homeostasis. - Give an example of how disruptions at a cellular level could affect an individual’s ability to maintain homeostasis. - Give an example of how disruptions to an ecosystem could impact homeostasis and the balance of the ecosystem.

39. Answer Key – LO 2.27 Which of the following scenarios consists of a homeostatic control system that has changed through evolution? I. As the physiological complexity of vertebrate animals increased, so did the need for more surface area to transport and exchange nutrients and oxygen in their circulatory system. Adaptations have allowed the development of large body size. II. Amphibians developed a second pumping circuit when the evolution of lungs created a major change in the pattern of the circulatory system. Blood is now pumped from the heart through the pulmonary arteries to the lungs and then is returned to the heart via pulmonary veins. III. When a person consumes alcohol, it reduces how much ADH (anti – diuretic hormone) they produce, therefore increasing how much urine is produced. IV. Mammals developed to have a 4 chambered heart due to the fact that oxygenated and deoxygenated blood does not mix. Deoxygenated blood from the body is pumped through the heart and to the lungs while oxygenated blood is returned to heart to be pumped to the rest of the body. I, II I, II, IV II, III II Biological systems are affected by disruptions, both internally and externally, that alter homeostasis. - Give an example of how disruptions at a cellular level could affect an individual’s ability to maintain homeostasis. - Give of example of how disruptions to an ecosystem could impact homeostasis and the balance of the ecosystem. At the cellular level a genetic disorder may affect an individual’s ability to maintain homeostasis. Specifically the metabolic disorder of Type I diabetes. Type I diabetes is a disorder where the pancreas is no longer producing adequate amounts of insulin to respond to changes in a person’s blood glucose level. Insulin levels must be maintained so through insulin replacement therapy, in conjunction with carbohydrate counting and careful monitoring of blood glucose concentration, the body can handle the glucose properly and keep itself balanced. Disruptions such as a natural disaster can affect homeostasis in an ecosystem. Debris and contamination of bodies of water, can lead to the salinization of nearby soil. This leads to a possible decrease in forest growth which could cause the biodiversity of a region to become unbalanced.

40. SP 6.1- The student can justify claims with evidence Explanation- One of the main components of Darwin’s theory, natural selection, was the interaction of a species with its environment. The different ways the animal responds to the environment can give one animal an advantage over the other. This makes the animal more fit to reproduce and pass on its genes to the next population. The variety of phenotypes are the driving force for these adaptations and the microevolution seen within a population. Phenotypic responses have three main patterns, stabilizing, directional, and disruptive selection. For example, a study on the desert mice in New Mexico showed that the sandy fur verse the dark fur came from a mutation altering the genotype of the animals. However, the dark mice would not have become prominent if there had not been a lava flow through the desert. The dark rock that resulted from the lava flow allowed the brown field mice an advantage over the sandy colored ones in this region, because they were not as easily spotted by predators. The mutation in the genes allowed for the different phenotype, and therefore the adaptation that allowed for reproduction and the passing of genes to the next generation. If you refer to the diagram below you will see another example of different phenotypes resulting from the same two genes. The genes control the size of the fly and the eye color, the different alleles cause different combinations of flies. LO 4.25- The student is able to use evidence to justify a claim that a variety of phenotypic responses to a single environmental factor can result from different genotypes within the population. Multiple Choice question: When scientists studied black desert mice from New Mexico and Arizona, they discovered that they were genetically different despite both looking the same. Both mice had ancestors that were white desert mice, what is the most likely explanation for the two populations to be black but not genetically the same. No two organisms are genetically the same due to crossing over in meiosis. The Arizona desert mice had black field mice as ancestors that mated with the white desert mice The mutation for the black fur occurred on different genes in the Arizona mice and the New Mexico mice. The black mice in New Mexico were heterozygous for dark fur, while the black mice in Arizona were homozygous Free Response Question: After a brief forest fire, scientists began to study the change in animal populations. They noticed that the big trees that remained were blackened by the smoke, and the moths that used to populate the area changed from commonly white to commonly dark brown. A) Identify one way in which the genotype altered the phenotype in this population. B) Identify another instance where there was a change in a species phenotype due to an environmental stimuli.

41. Multiple Choice question: When scientists studied black desert mice from New Mexico and Arizona, they discovered that they were genetically different despite both looking the same. Both mice had ancestors that were white desert mice, what is the most likely explanation for the two populations to be black but not genetically the same. No two organisms are genetically the same due to crossing over in meiosis. The Arizona desert mice had black field mice as ancestors that mated with the white desert mice The mutation for the black fur occurred on different genes in the Arizona mice and the New Mexico mice. The black mice in New Mexico were heterozygous for dark fur, while the black mice in Arizona were homozygous Free Response Question: • During the Industrial revolution in London, the pollution from the smoke towers coated the white poplar trees. Scientists began to notice that a lot of the white moths that used to be abundant were not as noticeable as the dark black moths. • A) Identify one way in which the phenotype altered the genotypic ratio in this population. • B) Identify another instance where there was a change in a species phenotype due to an environmental stimuli. A) The different color of the moth allowed for varying degrees of camouflage. Before the forest fire, the white winged moths were more plentiful because they could hide out on the bark of the trees and not be captured by predators. However, when the trees became covered in soot, the white moths stood out. They were killed quicker than the black moths and therefore did not reproduce and pass down their genes. The gene pool ratio changed when the dark moths became more abundant due to their ability to camouflage. The change in color could be due to dominate verse recessive alleles or due to a mutation in the moths RNA directly. B) One of the biggest examples of evolution is Darwin’s finches. Separated by water, the plants on the island all developed separately from each other. Some grew long flowers that required a long beak to suck nectar, and others were short requiring stunted beaks. Some of the finches had to evolve to crack nuts and their beaks are big a hard, while others have sharp small beaks used to crack seeds. The environmental stimuli is the food source; the different plants caused the finches to evolve and speciate away from each other. There are numerous explanations for the change in genotype which would cause the phenotype of the finches to be so starkly different. The answer is C, because both the populations originated from white mice meaning a mutation must have occurred for them to become black. The choice D is incorrect because the white allele would be dominate if the black mice came from it.

42. LO 3.22: The student is able to explain how signal pathways mediate gene expression, including how this process can affect protein production.SP 6.2: The student can construct explanations of phenomena based on evidence produced through scientific practices.Explanation: In a signal transduction pathway, a ligand binds to a receptor which will trigger relay proteins to transfer the stimulus through the cell, culminating in a response. For example, a hormone can bind to a G- protein linked/ tyrosine kinase/ ligand gated ion channel receptor, triggering many relay proteins to transfer the signal throughout the cell, allowing for the cell’s response to the ligand’s stimulus. A possible response could originate in the nucleus where RNA polymerase binds to the DNA, beginning transcription & translation so that the specific protein can be made to allow the cell to provide its response. When a steroid hormone passes through the plasma membrane and enters the nucleus, it can stimulate gene transcription and translation. These processes can allow protein production to continue or stop, depending on how much of the protein (read: how much/big of a response) is needed. This relates to both inducible and repressible operons on DNA, the release and subsequent function of hormones/neurotransmitters, and negative feedback loops. • M.C. Question: For gene expression to occur, which of the following would need to happen? • Testosterone travels to the nucleus and stimulates the transcription factors and allows the eventual production of the protein. • A cell is damaged, stimulating the mitotic division and repair of the cell. • DNA polymerase would need to bind to DNA to transcribe genes for eventual translation into proteins. • The ligand binds to the receptor which simultaneously releases the enzyme needed to express the ligand’s gene. • FRQ/LL Question: Suppose your body had a high blood- glucose concentration. Describe the way insulin would be generated to reduce the blood- glucose levels and how it would stop being generated. Figure 3.22.3

43. ANSWER KEY- LO 3.22 M.C. Question: For gene expression to occur, which of the following would need to happen? • Testosterone travels to the nucleus and stimulates the transcription factors and allows the eventual production of the protein. (Figure 3.22.1) • A cell is damaged, stimulating the mitotic division and repair of the cell. • DNA polymerase would need to bind to DNA to transcribe genes for eventual translation into proteins. • The ligand binds to the receptor which simultaneously releases the enzyme needed to express the ligand’s gene. FRQ/LL Question: Suppose your body had a high blood- glucose concentration. Describe the way insulin would be generated to reduce the blood- glucose levels and how it would stop being generated. The glucose molecules in the blood acts as a ligand and binds to beta cell receptors of the pancreas. The stimulus that this binding produces travels down a signal transduction pathway via relay proteins where the final protein enters the nucleus. This stimulates transcription factors and RNA polymerase to bind to DNA to transcribe it and make mRNA from the “insulin genes.” The mRNA exits the nucleus and goes through a ribosome for translation to create proteins needed to make insulin. Once the insulin was made, it would exit the cell and cause body cells to take up glucose and liver cells to store it as glycogen, thus decreasing blood- glucose levels. Negative feedback (Figure 3.22.2) stops this process because once blood- glucose levels are lowered, it will not bind to the receptors, causing the signal transduction pathway to end, which stops transcription and translation, which allows for the production of insulin- making proteins to end. Figure 3.22.2 Figure 3.22.3 Figure 3.22.1

44. LO 3.29: The student is able to construct an explanation of how viruses introduce genetic variation in host organisms.SP 6.2: The student can construct explanations of phenomena based on evidence produced through scientific practices. Explanation: Viruses insert their nucleic acid genome into the cell. Once in the cell, the viral genetic information either enters the lysogenic cycle and is incorporated into the genomic DNA of the cell or it replicates independently (i.e. extra-chromosomally). Both of these processes introduce genetic variation into the cell in the form of both the viral genome itself. The lysogenic process introduces genetic variation directly into the host genome in the form of viral DNA and also introduces genomic variation by disrupting host DNA at the site of integration. Retroviruses introduce RNA into a cell, which is converted into DNA by an reverse transcriptase and is then inserted into the host DNA. The DNA of DNA viruses can be incorporated directly into the host DNA introducing genetic variation Retroviruses introduce additional genetic variation because the DNA produced by reverse transcriptase is not subject to proofreading. RNA viruses have higher rates of mutation than DNA viruses too. Viral DNA is sequenced in labs, and radioactive probes based off of these sequences are used to identify the presence of viral genomes in cells or variation in the host genome, therefore identifying sites where variation has been introduced. Multiple Choice Question: Which virus would introduce the most genetic variation directly into the host DNA? • HIV (retrovirus) • Herpes virus (DNA virus) • Influenza A (RNA virus) D) T4 Bacteriophage (DNA virus) Free Response Question: DNA viruses introduce viral DNA that is incorporated into the host DNA and later translated into viral proteins and new viral DNA, as shown in figure 18.5 to the right. Retroviruses undergo a different viral process. Draw and label a diagram depicting how a retrovirus introduces genetic variation into the genome of a host organism.

45. Answer Key LO 3.29 Multiple Choice Question: Which virus would introduce the most genetic variation directly into the host DNA? • HIV (retrovirus) • Herpes virus (DNA virus) • Influenza A (RNA virus) D) T4 Bacteriophage (DNA virus) Free Response Question: Draw and label a diagram depicting how a retrovirus introduces genetic variation into the genome of a host organism. The diagram must show the virus binding to the cell and releasing viral RNA into the cell. The diagram must depict the transcription of RNA to DNA, and must show the newly transcribed DNA being incorporated into the DNA of the host cell. It is not necessary to include the process by which the retrovirus reproduces, although points will not be taken off for including this.

46. LO 2.10—The student is able to use representations and models to pose scientific questions about the properties of cell membranes and selective permeability based on molecular structure. • SP 1.4—The student can use representations and models to analyze situations or solve problems qualitatively and quantitatively. • SP 3.1—The student can pose scientific questions. • Explanation: The cellular/plasma membrane is fluid and able to allow specific molecules to pass through it. The membrane’s structure is mainly composed of a bilayer of amphipathic phospholipids, a polar phosphate head with two nonpolar fatty acid tails. The phosphate heads allow the cell to diffuse into water while the fatty acids are forced towards each other within the membrane due to the extracellular pressure and “repulsive” properties of nonpolar from polar molecules. The membrane remains fluid because the nonpolar fatty acid tails neither attract nor repel against each other; one of these tails is unsaturated with a double bond “kink” to keep the membrane fluid and stop solidification of the membrane. The nonpolar interior prevents ions, macromolecules and most polar molecules from entering the cell (such as sodium and sucrose) while allowing lipids and lipophilic (fat soluble) molecules to cross the membrane without the use of energy/passive diffusion. Water is also able to passively enter the cell because the molecules are small and the membrane has enough fluidity for water to move across the membrane. About twenty percent of the membrane’s mass is cholesterol, an amphipathic molecule, which keeps the membrane not too fluid at high temperatures and not too viscous at low temperatures. The membrane design also incorporates amphipathic proteins which act as ion/protein channels, glyco-lipids/-proteins which act as signal molecules and receptor molecules. • These integral proteins play a key role in the active diffusion of molecules and important ions which cannot pass the cellular membrane without assistance. The plasma membrane’s fluidity also allows it to accept or form vesicles which have the same membrane design; vesicles are used to transport large molecules into and out of the cell. • FRQ: A pharmaceutical company has developed a medicine which targets the interior of cells. Unfortunately the main chemicals of the medicine are unable to enter the cell. Describethree possible pathways for the chemicals to enter the cell. Explain in detail, how oneof these pathways functions. • M/C Question:What property of the cell membrane did evolution favor so that water molecules could passively enter the membrane, but other polar molecules could not? • The hydrophilic phosphate heads help cells diffuse in water • Osmosis occurs through hydrophilic protein channels • The unsaturated kinks create enough fluidity for osmosis to occur • Ion channels change the concentration to make the cell isotonic with the environment • Cholesterol bonds to water molecules as it passes through the cell Unsaturated “Kink”

47. FRQ: A pharmaceutical company has developed a medicine which targets the interior of cells. Unfortunately the main chemicals of the medicine are unable to enter the cell. Describe three possible pathways for the chemicals to enter the cell. Explain in detail, how one of these pathways functions. • Answer—The chemicals of the medicine can enter the cell through having a amphipathic coating, by having this coating the chemicals are able to be integrated through the cellular membrane because of the nonpolar part of the coating being lipophilic. By designing the chemicals to be recognized by a protein channel, the medicine could be diffused through the channel and past the plasma membrane. If the medicine was delivered through a vesicle then the chemicals could be transported into the cytoplasm by having the vesicle integrate with the cellular membrane. The vesicle method works by the way vesicles and cells have the same membrane structure; therefore, the phospholipids of the vesicle begin to integrate into the cellular membrane because of their amphipathic structure, releasing the chemicals from within the vesicle into the cytoplasm. This method could also work through the way cell will undergo phagocytosis and form vesicles with molecules from outside the cell; phagocytosis occurs because the membrane is fluid enough to “wrap” around the extracellular molecules and form a vesicle. Vesicle Vesicle membrane integrates with cell membrane Medicinal Chemicals • M/C Question: What property of the cell membrane did evolution favor so that water molecules could passively enter the membrane, but other polar molecules could not? • The hydrophilic phosphate heads help cells diffuse in water • Osmosis occurs through hydrophilic protein channels • The unsaturated kinks create enough fluidity for osmosis to occur • Ion channels change the concentration to make the cell isotonic with the environment • Cholesterol bonds to water molecules as it passes through the cell H2O

48. LO 2.34: The student is able to describe to role of programmed cell death in development and differentiation, the ruse of molecules, and the maintenance of dynamic homeostasis. SP 7.1: The student is able to connect phenomena and models across spatial and temporal scales. Explanation: The development of an organism is highly dependent on the programmed cell death, or apoptosis, of cells. Such processes take place in the beginning of temporal scales at early embryo development when morphogenesis takes place. This development forms the biological framework and patterns for appendages by inducing certain cells to die off so that appendages may form. Without this “cell-suicide” differentiation could not occur in a developing organism and biological patterns could not be observed. Later in life programmed cell death is a regular part of the cell cycle; it recycles organic molecules and ensures homeostasis by preventing excessive cell growth, or cancer. Therefore, without programmed cell death homeostasis could not be achieved across an organism’s temporal life span. Once broken down a cells leftover molecules are engulfed by neighboring cells for reuse ensuring that few molecules are wasted in the process. This recycling process occurs when the neighboring cell uses endocytosis to absorb and breakdown the dead cells membrane and organelles into the individual monomers for reuse in the living cell. For these reasons apoptosis helps to maintain the dynamic homeostasis of the cell; such as how dying cells die off to prevent the build of cells into tumors that could become a malignant tumor. Figure 1.1 See Figure 1.1

49. Multiple Choice Question: Which of the following processes is programmed cell death play a role in? Morphogenesis Killer T-Cell immune response Differentiation and Development of cells Formation of appendages for embryos Only ii i, ii and iv Only i, iii and iv All of the above Figure 1.2 In the organism C.elegansthe protein Ced-9 impairs apoptosis while it is active until a ligand signals it to become inactive causing cell death. What might be the consequences of a mutation which prevents the ligand binding to signal the Ced-9 on a developing embryo? What might the consequences on the health of an adult with this mutation? See Figure 1.2 for more info.

50. Answer Key- LO 2.34 Multiple Choice Question: Which of the following processes is programmed cell death play a role in? Morphogenesis Killer T-Cell active immune response Differentiation and Development of cells Formation of appendages for embryos Only ii i, ii and iv Only i, iii and iv- This is the correct answer because programmed cell death is helps form biological structures and differentiates cells in developing organisms. However, ii is not correct because programmed cell death is only a part of the passive immune system. All of the above Some of the possible consequences in the developing embryo would be the prevention of morphogenesis in the organism. Patterns could not be formed and thus the structure of appendages and other structures could not take place because the inhibition of the Ced-9 protein to shut-off. Also cell differentiation could not take place because only the same masses of cells would only be present and new cells could not induce specialization of the neighboring cells in the embryo. In the adult C. elegansone could expect to see the development of cancer because none of the cells are able to undergo programmed cell death. Therefore, and excess of cells in the form of tumors would be created and eventually lead to cancer and possible death of the adult.