Honors Biology: Final Exam Review

1. Honors Biology: Final Exam Review

2. Quarter #1

3. Chapter 1: The Scientififc Study of Life • Tools for Studying Life • Microscope – observe living cells • Compound Microscope – uses multiple lenses to magnify an image • Electron Microscope – uses a beam of electrons to create high quality, high magnification images • Balance – take mass of objects • Meter Stick – measure length of an object • Graduated Cylinder – measure volume of a liquid

4. Chapter 1: The Scientifc Study of Life • 8 Characteristics of Living Things: • 1. made up of cells (smallest unit of life) • 2. reproduce (sexually or aesexually) • 3. based on universal genetic code (DNA) • 4. grow & develop • 5. obtain & use materials/energy (metabolism) • 6. respond to their environment (stimuli) • 7. maintain stable internal environment (homeostasis) • 8. change over time (evolution)

5. Chapter 1: The Scientififc Study of Life • Organization in Biology • Ecosystem – group of organisms that live in the same place together with their non-living environment • Community – group of many populations that live in the same general area • Population – group of organisms of the same species that live in the same general area • Organism – individual life form • Organ System – group of organs that work together to complete a common task • Organ – a group of tissues that work together to complete a common task • Tissue – a group of cells that work together to complete a common task • Cell – the smallest unit of life • Molecule – a group of elements that are

6. Darwin & Evolution • Charles Darwin • Struggle for Existence – organisms compete against each other for necessary resources • Survival of the Fittest – those individuals best fit for their environment secure resources and survive • Adaptations – features or characteristics that increase an organisms chance of survival • Natural Selection – Organisms with beneficial adaptations survive and pass on beneficial traits to offspring

7. Darwin & Evolution • Factors Leading to Evolution • Members of the same species become separated from one another and develop independently (speciation) • Change in Environmental Factors – due to natural or unnatural causes • Migration of organisms to a new environment (natural or unnatural)

8. Chapter 2: The Chemical Basis of Life • Types of Chemical Bonds: • Ionic Bonds – attractions between ions of opposite charge; involve one atom donating an electron to another atom • Covalent Bond – the sharing of pairs of electrons to join molecules together (single, double, triple) • Hydrogen Bonds – weak bonds formed by the slightly charge regions on neighboring molecules; responsible for H2O’s unique properties

9. Chapter 2: The Chemical Basis of Life • Properties of Water (thanks to polarity) • Cohesion – the slight - charge of O attracts the slight + charge of H causing neighboring molecules to “stick” together (H bonds) • Adhesion– the slight charges of H2O molecules make it likely to “stick” to other things • Moderate Temperature – H bonds help H2O resist changes in temperature (HIGH boiling point) • Density – liquidH2O is MORE dense than solid H2O • Solvent – polarity helps H2O to break down other POLAR substances (non-polar substances like oils WILL NOT dissolve in H2O)

10. Quarter #2

11. Chapter 3: The Molecules of Cells • The Magic of Carbon • Because of its 4 valence electrons, carbon: • has a tendency to form covalent bonds • is able to make single, double, or triple bonds • is able to form VERY LONG chains • is able to bond with up to 4 other atoms • Macromolecules – large chain molecules (polymers) formed by subunits (monomers)

12. Chapter 3: The Molecules of Cells • 4 Main Organic (Carbon) Compounds: • Carbohydrates (polysaccharides) • Main source of energy • Made up of monosaccharides (sugars) ***Isomers – two molecules that has the SAME chemical formula, but DIFFERENT structures!

13. Chapter 3: The Molecules of Cells • 4 Main Organic (Carbon) Compounds: • Proteins • Control reaction rates, allow molecules in and out of cells, fight disease, make up muscles • Made up of amino acids • 20 + amino acids are used to express genes • each amino acid in a polypeptide chain is joined to by a peptide bond

14. Chapter 3: The Molecules of Cells • 4 Main Organic (Carbon) Compounds: • Lipids • Comprise membranes, energy storage, insulation • Made up of glycerol & fatty acids • Phospholipids make up bilayer of cell membrane

15. Chapter 3: The Molecules of Cells • 4 Main Organic (Carbon) Compounds: • Nucleic Acids • Store and transmit genetic information • Made up of nucleotides (sugar, phosphate group & nitrogenous base) • 5 Nitrogenous Bases: • Adenine (DNA & RNA) • Thymine (DNA ONLY) • Guanine (DNA & RNA) • Cytosine (DNA & RNA) • Uracil ( RNA ONLY)

16. Chapter 3: The Molecules of Cells • Dehydration Synthesis – joining of two or more organic molecules by REMOVING H2O • one molecule loses a hydroxyl (-OH); one loses a hydronium (-H) • covalent bonds form (sharing e-) • Hydrolysis – breaking apart of two or more organic molecules by ADDING H2O • one molecule gains a hydorxyl (-OH); one gains a hydronium (-H) • covalent bonds are broken

17. Early Earth • Stanley Miller & Howard Urey • showed that amino acids & other organic componds could have arisen from a lifeless Earth (chemical soup + lightening) • Evolution of oxygen-producing bacteria resulted in: • oxygenation of the atmosphere • massive extinction of many early anaerobic forms of life • extincting of bacteria unable to tolerate oxygen • anarobic bacteria engulfing aerobic bacteria for survival (endosymbiotic theory)

18. Chapter 4: A Tour of the Cell • Types of Cells • Prokaryotes – lack a “true” nucleus; lack membrane-bound organelles; bacteria • Eukaryotes – have a “true” nucleus; have specialized membrane-bound organelles • Plant Cells – contain cell walls, large vacuoles; chloroplasts; square-ish in shape • Animal Cells – contain only a cell membrane; contain centrioles; irregular in shape

19. Chapter 4: A Tour of the Cell • Plasma Membrane – “proteins floating in a sea of lipids” • PhsopholipidBilayer – primary component; made up of glycerol, phosphate group (polar & hydrophilic), and 2 fatty acid tails (non-polar & hydrophobic); arranged with tails facing the interior & heads facing exterior

20. Chapter 4: A Tour of the Cekk • Receptor Proteins – receive messages from outside the cell • Anchor Proteins – inside of membrane; aid in tethering organelles • Transport Proteins – transmembrane proteins that serves as passageways for larger molecules • Cholesterol – within bilayer; prevent solidifying of fatty acid tails • Glycoproteins & Glycolipids – used for identification

21. Chapter 4: A Tour of the Cell • Fluidity of the PhospholipidBilayer • ALL components of the bilayer are able to move freely about one another; this is because: • phosphoipids are unable to pack closely together • kinks in the fatty acid chains allow for movement • fatty acid chains are typically unsaturated (not solid at room temperature) • cholesterol prevents fatty acid tails from “sticking” • Permeability – ability to allow some molecules to pass through while blocking others (phenylthalanine & ammonia)

22. Chapter 4: A Tour of the Cell • Cellular Transport • Diffusion – “passive transport;” no ATP required;random movement of molecules from an area of HIGH concentration to an area of LOW concentration • Osmosis – diffusion of water from an area of HIGH H2O concentration to an area of LOW H2O concentration (osmoregulation– regulation of H2O inside a cell) • Active Transport – use of ATP energy to molecule molecules (or maintain molecules) AGAINST a concentration gradient

23. Chapter 4: A Tour of the Cell • Outside environment is HYPERTONIC (less H2O; more sucrose) to inside • Inside environment is HYPOTONIC (more H2O; less sucrose) to outside • THEREFORE H2O will LEAVE the cell 40 % Sucrose 60 % H2O 20 % Sucrose 80 % H2O ISOTONIC solutions – have equal concentrations of both SOLUTES and H2O

24. Chapter 4: A Tour of the Cell • In order to effectively transport nutrients to the cell, the cell must have a LARGE surface area to volume ratio

25. Chapter 4: A Tour of the Cell • Organelles of the Cell • Mitochondria – “powerhouse;” responsible for Cellular Respiration; resemble early prokaryotes; have their own DNA; reproduce independently; incorporated by heterotrophic prokaryotes • Chloroplast – responsible for Photosynthesis; resemble early prokaryotes; have their own DNA; reproduce independently; incorporated by heterotrophic prokaryotes

26. Chapter 4: A Tour of the Cell • Organelles of the Cell • Golgi Apparatus – modifies, sorts, and distributes proteins • Nucleus – controls all activity of the cell • Endoplasmic Reticulum – allows for intracellular transport • Ribosome – site of protein synthesis • Cytoplasm – cellular matrix

27. Chapter 5: The Working Cell • Enzymes – biological catalysts that speed up chemical reactions by lowering activation energy • Enzymes are recyclable – they are not used up or altered and can be used over and over • Enzymes are VERY specific – each enzyme only does ONE job; 3D structure determines its function • Enzymes have ideal temperatures and pHs - if an an enzyme’s environment changes, it will become denatured (change shape) and not be able to function

28. Chapter 5: The Working Cell • Exergonic Reactions – Products contain less energy than reactants; proceed spontaneously; release energy (heat) • Endergonic Reactions – Products contain more energy than reactants; DO NOT proceed spontaneously; absorb energy (heat)* • * feel cold to the touch • Exergonic and Endergonic reactions are usually coupled… the energy released from exergonic reactions can be used to power endergonic reactions!

29. Chapter 5: The Working Cell • Oxidation-Reduction (Redox) Reactions • LEO says GER • LOSE electrons OXIDATION • GAIN electrons REDUCTION

30. Quarter #3

31. Chapter 6: How Cells Harvest Chemical Energy • Cellular Respiration – the process by which energy is obtained from organic compounds (mitochondria) • ATP is produced by the joining of ADP molecules with inorganic phosphates • C6H12O6 + 6O2 6CO2 + 6H2O + ATP Energy • Lipids contain the MOST energy/gram, but our bodies do not readily break down these molecules • Carbohydrates contain the next highest amount of energy/gram and our bodies can readily break them down

32. Chapter 6: How Cells Harvest Chemical Energy • Step 1: Glycolysis(anaerobic) • A glucose molecule (C6H12O6) is broken down to create 2 molecules of Pyruvic Acid • Step 2: Kreb’s Cycle (aerobic) • Pyruvic Acid is broken down to form CO2 waste • Step 3: Electron Transport (aerobic) • High energy electrons are passed along a chain of electron acceptors to produce a charge gradient • Chemiosmosis • The movement of protons through ATP Synthase powers the joining of ADP and P to make ATP

33. Chapter 6: How Cells Harvest Chemical Energy • Fermentation – an anaerobic form of respiration employed by organisms in the absence of oxygen or by organisms unable to use/incorporate oxygen • LESS efficient at producing ATP molecules • Glycolysis CAN still proceed • Ethyl Alcohol and/or Lactic Acid may form is byproducts • 2 Net ATP will result from the process

34. Chapter 7: Photosynthesis: Using Light to Make Food • Leaf Structure • Stoma (stomata) – openings in the leaf that allow gasses, such as O2 and CO2 to pass in and out • Mesophyll – layer of leaf tissue that contains chloroplasts • Chloroplast – organelle that contains photosynthetic pigments (chlorophyll) that REFLECT green light and absorb other colors (giving plants their green color)

35. Chapter 7: Photosynthesis: Using Light to Make Food • Photosynthesis – the process by which energy from the sun is converted into starches • Organisms that make their own food in this manner are called photosynthetic autotrophs • 6CO2 + 6H2O C6H12O6 + 6O2 • Chloroplasts contain: • Grana – stacks of disc-shaped thylakoid membranes; site of Light-Dependant Reactions • Stroma – fluid portion; site of Carbon Fixation

36. Chapter 7: Photosynthesis: Using Light to Make Food • Light Dependant Reactions – H2O is broken down (released waste O2 gas) and high energy electrons are passed down the Electron Transport Chain creating ATP • End products: waste O2,& {ATP, NADPH, FADH2}  used to produce glucose during Carbon FIxation • Carbon Fixation – occurs when carbon in the form of CO2 is incorporated into organic storage molecules • End products: glucose

37. Chapter 8: Mitosis & Meiosis • Cell Cycle • Interphase • G1 – growth; normal function • S – synthesis; DNA is copied • G2 – additional growth; preparation for mitosis

38. Chapter 8: Mitosis & Meiosis • Cell Cycle • Mitosis • Prophase – DNA condenses; nuclear envelope breaks down; centrioles form • Metaphase – Chromosomes line up along equator of the cell • Anaphase – Spindle fibers pull chromatids apart • Telophase – nuclear division; 2 new nuclei form • Cytokinesis – cytoplasmic division; cell plate or cleavage furrow form and split cells

39. Chapter 8: Mitosis & Meiosis • Regulation of Cell Growth: • chromosomes DO NOT separate until spindle is attached to each centromere • cells are prevented from dividing unless they are anchored • cells DO NOT grow in the absence of growth factors • Mitosis DOES NOT occur until DNA Replication is complete

40. Chapter 8: Mitosis & Meiosis • Meiosis • reductive cell division used to create gametes (with ½ the genetic information of somatic cells) • create unique gametes due to: • crossing over (exchange of segments of genetic code by homologous chromosomes) • random positioning of chromosomes during Metaphase I • random fertilization

41. Quarter #4

42. Chapter 9: Patterns of Inheritance • Gregor Mendel – father of genetics • Heterozygous – two different alleles for a trait • Homozygous – two IDENTICAL alleles for a trait • Dominant – trait will be phenotypically expressed in either homozygous dominant or heterozygous genotypes • Recessive – trait will ONLY be expressed phenotypically in homozygous recessive individuals • Sex–Linked – alleles are found on the sex chromosomes (both X in females and one X in males – NOT FOUND ON Y CHROMOSOMES!)

43. Chapter 9: Patterns of Inheritance • A Basic Punnett Square • Dimples (d) are a recessive trait. Two heterozygous individuals want to have children together… • What is the chance their child will have dimples? • What is the expected genotypic ratio? • What is the chance their child will be without dimples? • What is the expected phenotypic ratio?

44. Chapter 9: Patterns of Inheritance • A Sex-Linked Punnett Square • Hemophilia is a sex-linked, recessive trait. A non-carrier female and a hemophiliac male want to have children… • What is the chance their child will have hemophilia? • What is the chance any of their children will be carriers? • What are the genotypes of the parents? • What are the genotypes for a hemophiliac male? female?

45. Chapter 9: Patterns of Inheritance • Hardy-Weinberg Equilibrium • To be in equilibrium • NO mutations must arise • NO natural selection can occur • NO migration can occur • There must be a HUGE population • Completely random mating must occur

46. Chapter 9: Patterns of Inheritance • Hardy-Weinberg Equation • p + q = 1 • Where… • p = frequency of the dominant allele • q = frequency of the recessive allele • p2 + 2pq + q2 = 1 • Where… • p2 = frequency of the AA genotype • 2pq = frequency of the Aa genotype • q2 = frequency of the aa genotype

47. Chapter 9: Patterns of Inheritance • Hardy-Weinberg Equation • You have sampled a population in which you know that the % of the aa (albino) genotype is 36%. • What is the allele frequency for albinism? • What % of the population would be homozygous for “normal” pigmenting?

48. Chapter 10: Molecular Biology of the Gene • DNA Structure • Hydrogen Bonds connect nitrogenous bases (A  T & G  C) • = deoxyribose (sugar) • = phosphate

49. Chapter 10: Molecular Biology of the Gene • Replication • What? Copying of genetic material • When? Prior to cell division (mitosis) • Where? inside the nucleus • Why? to ensure all new cells have copies of genetic information • How? Base-pairing rule! (A T, G  C) • DNA Helicase unzips the double helix. • DNA Polymerase adds on new nucleotides (base pairing) & then “proofreads” the new strands

50. Chapter 10: Molecular Biology of the Gene • Replication • What? Copying of genetic material • When? Prior to cell division (mitosis) • Where? inside the nucleus • Why? ensure all new cells have copies of genetic info • How? Base-pairing rule! (A T, G  C) • DNA Helicase unzips the double helix. • DNA Polymerase adds on new nucleotides (base pairing) & then “proofreads” the new strands • DNA Ligase joins together the completed Okazaki fragments of the discontinuous (lagging) strand