MATTER AND ENERGY TRANSFER

1. MATTER AND ENERGY TRANSFER • The atoms we are built out of cycle through the ecosystem constantly. Describe in words or labeled drawings how each of the following atoms/molecules cycles through our ecosystems: • Pictures of each of these can be found in the book. Understand CONCEPTS don’t worry about specific chemical changes

2. Cycles of matter (C, N, H, O) • Carbon • Nitrogen • Water • Once in an organism, what are these atoms used for? • To build new cells

3. Moving matter and energy • How are these atoms passed from one organism to the next? • When we eat a plant the atoms that make up the plant get digested and then our body uses them to build new cells for us. • How can these atoms be returned to the non-living parts of our ecosystem? • When we die all our atoms are returned to the soil through decomposition or released into the atmosphere (CO2)

4. Can we make new matter • NO….NO…..NO • We just recycle the matter that is here. Living things today are made of the exact same atoms that living things were made of back in dinosaur times

5. What about energy? • The initial source of all energy is the SUN • How is this true even for strict carnivores? • The sun provides energy for the plants to photosynthesize. Herbivores eat the plant and energy gets transferred to them. Then the carnivores eat the other animals and the energy is transferred to them.

6. The energy pyramid • The shape of the pyramid implies there is “less” at the top. “Less” what and why is this necessary for success of the ecosystem? • Less energy and less biomass (atoms!) • WHY?: because it is the lower levels that feed and support the upper levels. Need to have more food than eaters or else you run out.

7. What does a food web demonstrate? • Flow of energy and matter from the producers through the apex consumers Impact of removal of a single species: • Species that depend on the removed species (predator) for food will decline in population • Species that the removed species consumes (prey) will become over populated causing a shortage of their (the prey’s) food source.

8. Amt of energy passed from one trophic level to the next • 10% is passed from one level to the next • What happens to the rest? • Ultimately becomes thermal energy (heat)

9. Biologically, how do we extract energy from food? • Cellular respiration: • Key enzymes in the cell along with the mitochondria break the glucose down into CO2 and Water and transfer the energy to ATP molecules. • Other foods, like protein and fats are first converted into types of sugars that can go through the same cellular respiration process.

10. Diagram of PS and Respiration

11. Three forms of energy in an ecosystem • Light – sun • Chemical – glucose • Thermal – body heat released after using energy

12. Two purposes of food: • Energy (we make ATP) • Building materials • We use atoms and rearrange them to make cells for “us”. • (also specific nutrients that are used directly like vitamins, amino acids, minerals)

13. Why does an organism NOT disintegrate when it is alive? • A constant supply of energy keeps our body maintained • When we die the energy supply ceases and body processes no longer are maintained.

14. Interdependence of 2 or more Organisms • Symbiosis • Three forms • Mutualism • Commensalism • Parasitism

15. Problem 1. • In an experiment, chickens were fed grain that contained a chemical marker in its proteins. The presence of the marker can be detected in organisms. Which of the following is the most reasonable prediction from this experiment? a. The marker will only be found in the grain. b. Both chickens and wolves will have the marker c. Wolves will have the marker, but chickens will not. d. The marker will only be found in the animals’ wastes.

16. Problem 2 • What two things are passed from one organism to another in the food chain? • Energy and Heat • Matter and Atoms • Energy and Matter • Water and food

17. Problem 3 • Which types of organisms assist in cycling atoms back into the soil? • Producers • Primary consumers • Apex consumers • Decomposers

18. Problem 4 • . Which hypothesis would most likely be tested using this setup? • A. Green water plants release a gas in the presence of light. • B. Roots of water plants absorb minerals in the absence of light • C. Green plants need light for cell division. • D. Plants grow best in the absence of light.

19. Problem 5 • At position Y, carbon is most likely to be in which of the following forms? • A. protein • B. carbon solid • C. carbohydrate • D. carbon dioxide

20. Problem 6 • Which of the following diagrams correctly represents an energy pyramid from this web? B

21. Part C Interdependence • Define the following terms in relationship to their position in the hierarchy of ecosystems • Populations: all of one single species that lives in a region • Communities: all of the living things in a region (multiple species combined) • Ecosystems: All of the living things AND the non-living things they depend on • Biomes: All the ecosystems at a particular climate • Biospheres: The entire region of the planet in/on which life can exist

22. Food Webs • Explain how each organism in a food web can be dependent on eachother. • They can depend on each other for food, reproduction, habitat selection; no organism can survive entirely on its own.

23. What does the term symbiosis mean? • Relationship between two organisms that is necessary for the survival of one or both the species. • THREE TYPES • Mutualism – win/win • Commensalism – win/no effect • Parasitism – win/lose

24. Human Impact on Environment • List five activities and explain HOW • Excessive use of fossil fuels – build up of CO2; traps extra heat; global warming • Over developing wooded areas – destroys habitats of organisms; impacts the food chain • Deforestation – removes trees which reducing oxygen production and CO2 removal • Excessive use of chemicals like CFC’s – depletion of the ozone layer; more harmful UV rays hitting earth • Pollution of lakes and rivers – damages water life; contaminates water supply

25. When left alone (naturally) • How does an ecosystem balance itself to keep all the organisms at the top of the food chain from wiping out all the organisms below? • As a consumer increases the food supply of that consumer decreases; eventually there will not be enough food and the consumers will die off; As the consumers die, the food supply is rebuilt and so on

26. Problem 1

27. Problem 2 • If many trees are removed from a forest, what is the most immediate effect on the carbon cycle in that forest? • A. increased rates of decomposition B. decreased use of atmospheric CO2 • C. decreased combustion of fossil fuels D. increased production of organic compounds

28. Heredity and Reproduction • Organisms reproduce, develop, and have predictable life cycles. • Organisms contain genetic information that influences their traits, and they pass this on to their offspring during reproduction.

29. Heredity and Reproduction • 1. Genes are segments of DNA molecules located in the chromosome of each cell. DNA molecules contain information that determines a sequence of amino acids, which result in specific proteins. • 2. Inserting, deleting, or substituting DNA segments can alter the genetic code • 3. An altered gene may be passed on to every cell that develops from it. The resulting features may help, harm, or have little or no effect on the offspring’s success in its environment. • 4. Sorting and recombination of genes in sexual reproduction result in a great variety of possible gene combinations in the offspring of any two parents

30. Basic Information • According to the central dogma of all living things: _DNA__contains the master copy of all our information. • This information is broken up into sections, or recipes, called ___genes__. • Each gene contains the directions to make a single __protein_____ by linking together the proper sequence of _amino acids__. • Before building a protein, a temporary copy of the single recipe must be made. This copy is called __RNA_. • Ultimately it is the __protein_ that gives you the traits that we have and the __genes/DNA_ that teaches us how to make them.

31. DNA • Kept in the NUCLEUS • Wound up DNA: • Chromosomes

32. Mutation • Change in the DNA • What problems does it cause? • Since the DNA contains the directions to make proteins, changing the DNA could change the protein; Can cause diseases, can have no effect or can improve the function of a protein;

33. What types of changes are considered mutations? • Insertions – add a nucleotide; • Deletions – remove a nucleotide; • Substitution – swap one nucleotide for another • ANY CHANGE IN DNA IS A MUTATION!

34. Effect of a mutation on future cells • Since all the DNA is copied before cell division, a mutation in the parent cell will be copied and passed to the new cells. • Mutations do not have to be negative. They can be helpful or have no effect.

35. What is genetic variation and why is it important? • Genetic variation is diversity within or between species because of their DNA differences. • IMPORTANCE: It is necessary to have variation so that natural selection can occur. • Differences give individuals different ability to survive and reproduce. This allows for evolution

36. Three things that increase genetic variation in a population • Mutation • Sexual reproduction – mixing the DNA of two individuals • Recombination/crossing over – mixing up your own DNA to make various different reproductive cell • Migration – introduction of new alleles into a population from a different population

37. Genetic Variation • Which process listed above also explains how one set of parents can seemingly have an infinite number of different children? • Recombination

38. Problem 1 • Fireflies produce light inside their bodies. The enzyme luciferase is involved in the reaction that produces the light. Scientists have isolated the luciferase gene. • A scientist inserts the luciferase gene into the DNA of cells from another organism. If these cells produce light, the scientist knows that which of the following occurred? • A. The luciferase gene mutated inside the cells. • B. The luciferase gene was transcribed and translated. • C. The luciferase gene destroyed the original genes of the cells. • D. The luciferase gene moved from the nucleus to the endoplasmic reticulum

39. Problem 2 • Which of the following best describes the result of a mutation in an organism's DNA? • A. The mutation may produce a zygote. • B. The mutation may cause phenotypic change. • C. The mutation causes damage when it occurs. • D. The mutation creates entirely new organisms.

40. Problem 3 • The diagram shows the positions of the genes for flower color and stem length in a pea plant. • For these two genes, what is the maximum number of different allele combinations that can be formed normally in gametes produced from this cell? 2 4 6 8 PT Pt pT pt

41. Problem 4 • If the DNA is mutated which of the following statements is true? • ALL other cells in the body will have the same mutation. • All proteins in the cell will be mutated • Any proteins, RNA or cells that come from the mutated DNA will have the mutation • The cell will fix the mutation and nothing will happen.

42. Problem 5 • Which of the following populations is likely to have a high degree of genetic diversity? • An asexual population of bacteria with a very low mutation rate (asexual = NO VARIATION) • Sexually reproducing species where crossing over is frequent • A population of sheep created by cloning (NO VARIATION) • A very small population of sexually reproducing species. (SMALL POPULATIONS HAVE LOW NUMBER OF VARIATIONS)

43. EVOLUTION AND DIVERSITY • Sometimes, differences between organisms of the same kind provide advantages for surviving and reproducing in different environments. • These selective differences may lead to dramatic changes in characteristics of organisms in a population over extremely long periods of time.

44. KEY LEARNINGS • 1 New traits may result from new combinations of existing genes or from mutations of genes in reproductive cells within a population • 2. Molecular evidence (e.g., DNA, protein structures, etc.) substantiates the anatomical evidence for evolution and provides additional detail about the sequence in which various lines of descent branched • 3. The principles of evolution (including natural selection and common descent) provide a scientific explanation for the history of life on Earth as evidenced in the fossil record and in the similarities that exist within the diversity of existing organisms 

45. Key Learnings 4. Evolution occurs as a result of a combination of the following factors: A. Ability of a species to reproduce B. Genetic variability of offspring due to mutation and recombination of genes C. Finite supply of the resources required for life D. Natural selection, due to environmental pressure, of those organisms better able to survive and leave offspring

46. Evolution is defined as: • How a population changes over long periods of time • What key scientist is credited with the bulk of our understanding about evolution? • DARWIN

47. Physical or molecular features used to support evolution and shared common ancestors: • DNA/Protein structures (molecular) – more similar the sequences or structure the more closely related two organisms are • Anatomy – similar body structures can provide information about relationships and ancestry • Embryonic development – the stages we go through during development can be informative • Fossils – can tell us approximately how long ago an organism lived

48. How does natural selection work? • Requires presence of variation! • Environmental stress (limited food and/or other resources) must be present • Competition for resources occurs - and because they are different some are better at competing that others • Survival of the fittest – the organisms best adapted win the competition and increase their chances of surviving and reproducing • Descent with modification – winners reproduce more and the next generation consists of more individual’s with the “winner’s” traits that the “loser’s” traits.

49. How does genetic variation promote evolution? • Allows organisms to be on different playing fields as far as competition goes. • Increases the chances that there is a “super” trait out there than will give the organism a survival advantage

50. Does evolution = new species? • No. EVOLUTION = a shift in the frequency of certain alleles (variations of genes) or traits • A population does NOT have to become a separate new species (or split and become two species) in order for it to be “evolving”.