Biology Final Exam Study Guide Answer Key

GENERAL BIOLOGY I / REVIEW QUESTIONS NOTE: This set of questions is just to help you concentrate on important topics you should know by the end of this course. This in NO WAY means that the final exam’s content will be just from the questions in this list. Chapter 1 (Exploring Life) 1. Diagram the hierarchy of structural levels in biological organization from the simplest to the most complex level. ○ Atoms ○ Molecules ○ Organelles ○ Cells ○ Tissues ○ Organs ○ Organ System ○ Organism ○ Population ○ Community ○ Ecosystem ○ Biosphere 2. What are the two major dynamic processes of any ecosystem? Nutrients Cycle and Energy Flow 3. Distinguish between prokaryotic and eukaryotic cells. Prokaryotic - small, lack membrane-enclosed nucleus, and organelles. (Bacteria and Archaea) Eukaryotic - large, have membrane enclosed nucleus and organelles. (Protists, Plants, Fungi, Animals) 4. Distinguish between positive and negative feedback. Negative Feedback - accumulation of end product of a process slows down that process. Positive Feedback - end product speeds up its own production 5. What is homeostasis? A steady-state physiological state of the body 6. What are the three domains of life? Bacteria, Archeas, Eukarya 7. List and distinguish among the three kingdoms of multicellular eukaryotic life. Plantae - most plants produce their own sugars and food by photosynthesis Fungi - most fungi are decomposers that absorb nutrients by breaking down dead organisms and organic waste Animalia - animals obtain food by ingesting other organisms 8. What is the controlled scientific experiment? An experiment designed to compare an experimental group and control group which differ in the one favor the experiment is designed to test Chapter 2 (The Chemical Context of Life) 9. Distinguish between an element and a compound. Element - a substance that cannot be broken down into other substances by chemical reactions. There are 92 naturally occurring elements and about 25 of these are essential for life. Compound - a substance that consists of two or more elements in a fixed ration. Ex. Table salt NaCl (Sodium Chloride). Sodium is a metal and Chlorine is a gas, but they can combine to for table salt. 10. Distinguish between each of the following pairs of terms: a. neutron and proton. Neutron - electrically neutral Proton - positively charged b. atomic number and mass number Atomic Number - equals the number of protons in that elements nucleus Atomic Mass - protons + neutrons 11. Explain how the atomic number and mass number of an atom can be used to determine the number of neutrons. Subtracting the atomic number from the atomic mass of element. Atomic Number - Atomic Mass = Neutrons 12. Explain how two isotopes of an element are similar. Explain how they are different. Two isotopes of an element have the same number of protons and electrons. Same element but different number of neutrons. They differ in the number of neutrons they have. 13. Distinguish among nonpolar covalent, polar covalent and ionic bonds. Nonpolar Covalent Bond - when electrons in a covalent bond are shared equally. Ex.Bond between Carbon and Hydrogen CH4. Polar Covalent Bond - when two atoms that differ in electronegativity bond and they don’t share the electron pair equally. Ex. bond between hydrogen and oxygen H2O. Ionic Bond - can form if two atoms are so unequal in their attraction for valence electrons that one atom strips and electron completely from the other. Ex. Sodium has 1 valence electron and Chlorine has 7 so sodium transfers its 1 chlorines 7 and both elements complete their valence shells. 14. Distinguish between hydrogen bonds and van der Waals interactions. Hydrogen Bonds - form when hydrogen atom that is already covalently bonded to one electronegative atom is attracted to another electronegative atoms. Ex. The electronegative partners are usually Nitrogen and Oxygen. Van der Waals Interactions - occur between transiently positive and negative regions of molecules. 15. Define the terms energy, potential energy, and kinetic energy. Energy - the ability to do work Potential Energy - the energy that matter stores because of its position or location Kinetic Energy - the energy of motion, observable as the movement of an object, particle or set of particles Chapter 3 (Water and the Fitness of the Environment) 16. With the use of a diagram or diagrams, explain why water molecules are: a. Polar - the oxygen end of the water molecule has a partially negative charge and the hydrogen molecule has partially positive charge. b. capable of hydrogen bonding with four neighboring water molecules The slightly negative region of some water molecules can form hydrogen bonds with a slightly postive regions of surrounding water molecules. 17. List four characteristics of water that are emergent properties resulting from hydrogen bonding. ○ Organisms depend on the cohesion of water molecules ○ Water moderates temperatures on Earth ○ Oceans and lakes don’t freeze solid because ice floats ○ Water is the solvent of life 18. Define cohesion and adhesion. Cohesion - a collection of hydrogen bonds that bond water together. They play a key role in transporting water and dissolved nutrients against gravity in plants. Ex. water and nutrients absorbed by the roots from the soil are transported up to the stem and into the leaves because of cohesion. Adhesion - the clinging of one substance to another. Ex. water clinging to the wall of vessels in plants. 19. Explain the following observations by referring to the properties of water: a. Insects like water striders can walk on the surface of a pond without breaking the surface. Surface tension. Water has a greater surface tension than other liquids because hydrogen bonds among surface water resist stretching or breaking the surface. Water behaves as if is covered by an invisible film. b. Ice floats on water. Water is less dense as a solid than as a liquid (unusual). Most materials contract as the solidify but water expands. The surface layer of ice insulates the liquid water below preventing it from freezing and allows life to exist under the frozen surface. c. Humans sweat to cool themselves on hot days. Evaporative cooling explains human sweating to cool off. As a liquid evaporates, the surface of the liquid that remains behind cools. Evaporation of sweat in mammals prevents territorial organisms from overheating. 20. Distinguish among a solute, a solvent, and a solution. Solute - substance that is dissolved Solvent - dissolving agent Solution - liquid that is completely a homogenous mixture of two or more substances. 21. Distinguish between hydrophobic and hydrophilic substances. Hydrophobic - repels water Ex. oil Hydrophilic - attracts water Ex. cotton 22. Define acid, base, and pH. Acid - substance that increases that hydrogen ion concentration in a solution. The addition of an acid makes a solution more acidic. Ex. Hydrochloric Acid Base - substance that reduces hydrogen ion concentration in a solution. The addition of base make a solution more alkaline. Ex. Sodium Hydroxide pH - measure of hydrogen ions concentration in a solution. Each whole number on the scale indicates a tenold change in acidity. pH of 7 = neutral pH less than 7 = acidic pH greater than 7 = basic 23. Explain how acids and bases may directly or indirectly alter the hydrogen ion concentration of a solution. 24. Using the bicarbonate buffer system as an example, explain how buffers work. To maintain cellular pH Values at a constant level, biological fluids have buffers, which resist change in the pH of solution when H+ or OH- is added to the solution. Chapter 4 (Carbon and the Molecular Diversity of Life) 25. Explain how carbon’s electron configuration accounts for its ability to form large, complex, and diverse organic molecules. Carbon has 4 valence electrons which allow it form covalent bonds with many other atoms to form a tetravalence which makes large complex molecules possible. 26. Describe the basic structure of a hydrocarbon and explain why these molecules are hydrophobic. Hydrocarbons are organic molecules that consist of only one carbon and hydrogen atoms. They are hydrophobic because they are covered in hydrogen atoms and are not polar like water molecules. 27. Distinguish among the three types of isomers: structural, geometric, and enantiomer. Structural Isomers - have the same molecular formula but differ in the covalent arrangement of atoms and or the location of the double bond. Geometric Isomers - have the same covalent partnerships but differ in the spatial arrangement of atoms around a carbon-carbon double bonds. Enantiomers Isomers - molecules that are mirror image of each other. They possible when four atoms or groups of atoms are bonded to an asymmetrical carbon. 28. Name the major functional groups found in organic molecules. Draw and describe the basic structure of each functional group. Hydroxyl Methyl Carboxyl Amino Phosphate Sulfhydryl Chapter 5 (The Structure and Function of Macromolecules) 29. List the four major classes of macromolecules. Carbohydrates, lipids. Proteins, and nucleic acids 30. Distinguish between monomers and polymers. Polymers - used to build macromolecules, they are a long molecule consisting of many similar or identical building blocks built by covalent bonds. Monomers - the repeated units (small molecules) that make up a polymer. 31. Distinguish between condensation and hydrolysis reactions. Condensation - happens when monomers are connected by covalent bonds that form through a loss of water. Hydrolysis - the covalent bonds that connect monomers in a polymer are disassembled by hydrolysis, (bonds are broken through the addition of water) a reaction that is the reverse of dehydration 32. Distinguish among monosaccharides, disaccharides, and polysaccharides. Monosaccharides - simple sugar containing between 3-7 carbon atoms Ex. glucose C6H12O6 major source of carbon and energy for most living organisms. Disaccharides - 2 simple sugars covalently bonded together through glycosidic covalent bonds. Ex. glucose + fructose = sucrose + H2O, glucose + galactose = lactose + H2O, glucose + glucose = maltose + H2O Polysaccharides - formed when hundreds of simple sugars are combined by dehydration synthesis, they are often hydrophobic and are important molecules that are organisms use to store energy and make cellular structures like cell walls. Ex. starch - used by plants to store excess glucose, cellulose 33. Describe the building-block molecules, structure, and biological importance of fats and phospholipids. Fats are constructed of two kinds of smaller molecules; glycerol (a 3-carbon alcohol with a hydroxyl group attached to each carbon) and fatty acids (a carboxyl group attached to a long carbon skeleton, often 16-18 carbons long) fats are important because hey store large amounts of energy. Phospholipids are the major component of all cell membranes. They are made up of two fatty acid attached to glycerol and phosphate group at the third position. 34. Distinguish between saturated and unsaturated fatty acids. Saturated fats - no carbon. Carbon double bonds, saturated with hydrogens at every possible position, a straight chain, most animal fats are saturated and saturated fats solidify at room temperature. Unsaturated fats - one or more carbon. Carbon double bonds formed by the removal of hydrogen atoms from the carbon skeleton. Plant and fish oils are unsaturated fats because the kinks caused by double bonds keep the oil from being able to pack tightly enough to solidify at room temperature 35. Distinguish between a protein and a polypeptide. A protein consists of one or more polypeptides folded and coiled into a specific conformation. Each one has a 3D shape. They account for more than 50% of the dry mass in cells. Polypeptides are the two or more amino acids bound together to form a protein. 36. List the four major components of an amino acid. Explain how amino acids may be grouped according to the physical and chemical properties of the R group. ○ Hydrogen Atom ○ Carboxyl Group ○ Amino Group ○ Variable R Group Non-polar - hydrophobic polar = hydrophilic Negative charge - acidic Positive charge = basic 37. Name two types of secondary protein structure. What type of chemical bonds stabilizes the secondary structure. Helix = hydrogen bonding B pleated sheet = hydrogen bonding ○ Hydrogen Bonds ○ Ionic Bonds ○ Hydrophobic Reaction ○ Vans Der Waals interaction? ○ Covalent Bonds (disulfide bridges) 38. What types of chemical bonds stabilize the tertiary protein structure? These bonds are formed between the R-groups of the amino acids OR the polypeptide backbone (choose one answer). R-groups of the amino acids 39. List conditions under which proteins may be denatured. ○ Alterations in pH ○ Salt Concentration ○ Temperature ○ Chemicals that disrupt the bonding that maintains a protein’s shape 40. List the major components of a nucleotide. ○ Nitrogenous Base ○ Pentose Sugar ○ Phosphate Group 41. Distinguish between ribose and deoxyribose The only difference between these two sugars is the lack of an oxygen atom on carbon 2 in deoxyribose 42. List three basic structural differences between DNA and RNA. ○ DNA has the bases adenine, guanine, cytosine, and thymine; RNA has adenine, guanine, cytosine, and uracil. ○ DNA has the sugar ribose deoxyribose; RNA has the sugar ribose ○ DNA is double stranded; RNA is single stranded 43. What are the building blocks of each of the following macromolecules: a. Carbohydrates - carbon, hydrogen, and oxygen b. Fats - carbon, hydrogen, oxygen, nitrogen, and phosphorus c. Proteins - carbon, hydrogen, oxygen, and nitrogen d. The nucleic acids DNA and RNA - nitrogenous base, phosphate, pentose sugar Chapter 6 (A Tour of the Cell) 44. Distinguish between magnification and resolving power of a microscope. Magnification is the ratio of an object's image to its real size. Resolving power (resolution) is a measure of image clarity. 45. Describe the structure and function of the nuclear envelope, including the role of the pore complex. The nuclear envelope is a double membrane perforated by pores. The pre complex lines each pore, regulating the passage of certain large macromolecules and particles. 46. Explain how the nucleolus contributes to protein synthesis. In the nucleolus, ribosomal RNA (rRNA) is synthesized and assembled with proteins from the cytoplasm to form large and small ribosomal units. 47. Describe the structure and function of a eukaryotic ribosome. Ribosomes containing rRNA and protein are the cuellar components that carry out protein synthesis 48. Distinguish between free and bound ribosomes in terms of location and function. Free ribosomes - suspended in cytosol and synthesize proteins that function within the cytosol. Bound Ribosomes - attached to the outside of the endoplasmic reticulum or nuclear envelope and synthesize proteins that are inserted into membranes, packaged into organelles or exported from the cell 49. List the components of the endomembrane system and describe the structure and functions of each component. Nuclear Envelope - surrounds nucleus, composed of two layers and has numerous openings for nuclear traffic. Endoplasmic Reticulum - tubular network fused to nuclear membrane, goes through cytoplasm onto cell membrane, stores, separates, and serves as cell’s transport system. Smooth ER - lacks ribosomes. Rough ER - ribosomes embedded in surface. Golgi Apparatus - protein “packaging plant”. A membrane structure found near nucleus. It’s composed of numerous layers forming a sac Lysosomes - digestive “plant” for proteins, lipids, and carbs. It transports undigested material to cell membrane for removal. They vary in shape depending on process being carried out. Cell breaks down if lysosome explodes. Vacuoles - membrane-bound sacs for storage, digestion, and waste removal. Contains water solution and contractile vacuoles for water removal (in unicellular organisms) Plasma Membrane - outer membrane that controls cellular traffic. Contains proteins (left,gray) that span through the membrane and allow passage 50. Compare the structure and functions of smooth and rough ER. Smooth ER - smooth surface, synthesis of lipids, metabolism of carbohydrates, calcium storage, detoxification of drugs and poisons. Rough ER - has ribosomes attached to its surface, and ids in synthesis of secretory and other proteins from bound ribosomes; adds carbs to glycoprotein; produces new membranes 51. Describe the function of the lysosomes. ○ Digestive “plant” for proteins,s lipids, and carbohydrates ○ Transports undigested material to cell membrane for removal ○ Vary in shape depending on process being carried out ○ Cell breaks down if lysosome explodes 52. Name three different kinds of vacuoles, giving the function of each kind. ○ Food Vacuole - enzymes digest food ○ Contractile Vacuole - found in freshwater protists, pump excess water out of the cell to maintain the correct amount of salts ○ Central vacuole - found in many mature plant cells; stockpiling proteins, disposing metabolic by products, holding pigments, boring defensive compounds that protect the plant against herbivores, plays a major role in the growth of plant cells 53. Briefly describe the energy conversions carried out by mitochondria and chloroplasts. Mitochondria - cellular respiration - generate ATP by extracting energy from sugars, fats, and other fuels with the help of oxygen. Chloroplasts - photosynthesis - convert solar energy energy to chemical energy and synthesize new organic compounds such as sugar from CO2 and H2O. 54. Describe the structure of a mitochondrion. A mitochondrion contains outer and inner membranes composed of phospholipid bilayers and proteins. The two membrane, however have different properties because of this double-membraned organization, there are five distinct compartments within the mitochondrion membrane, the intermembrane space (the space between the outer and inner membranes), the inner mitochondrial membrane, cristae space (formed by infoldings of the inner membrane), and matrix (space within the inner membrane) 55. Describe the structure of a chloroplast. Chloroplasts are sites of photosynthesis. These double-membrane bound organelles enclosed additional membranes called thylakoids which possess an interior space. They are stacked to form grana, which are suspended in the stroma of the chloroplasts. 56. Explain the roles of peroxisomes in eukaryotic cells. Peroxisomes participate in the metabolism of fatty acids and other metabolites. They have enzymes that rid the cell of toxic peroxides. They have a single lipid bilayer membrane that separates their contents from the cytosol and contain membrane critical for various functions. 57. Describe the functions of the cytoskeleton. A cytoskeleton acts as a framework that gives the cell its shape and protects it to a certain degree. It also enables cellular motion. 58. Explain how the ultrastructure of cilia and flagella relates to their functions. The ultrastructure is made up of dyneins, which are like “feet” and enable the cilia and flagella to “walk”, which contributes to their specialized movement. 59. Name the intercellular junctions found in plant and animal cells and list the function of each type of junction. Plasmodesmata - small channels in the plant cell that allows certain molecules to pass Tight Junctions - prevents the passage of molecules and ions through space between animal cells. This pathway provides control over what substance are allowed through Desmosomes - a type of intercellular junction in animal cells that function as a rivet (anchor) Gap Junctions - creates a gap that allows various molecules and ions to pass freely between cells (it basically the plasmodesmata of animal cells) Chapter 7 (Membrane Structure and Function) 60. Explain why phospholipids are amphipathic molecules. Phospholipids have both hydrophobic and hydrophilic regions. The molecules in its bilayer are arranged so the hydrophobic fatty acid tails are sheltered from water while the hydrophilic fatty acids interact with water. 61. Describe the fluidity of the components of a cell membrane and explain how membrane fluidity is influenced by temperature and membrane composition. Many of the membrane proteins drift in the phospholipid bilayer. Some move directional while other never mover because they are anchored to the cytoskeleton. When temperature become cooler, the membranes become solid and the phospholipids are packed more tightly. Membranes with more unsaturated fats are more fluid than those with more saturated fats. 62. Distinguish between peripheral and integral membrane proteins. Peripheral proteins are not embedded in the lipid bilayer at all, but are loosely bound to the surface of the protein and can be connected to integral proteins. Integral proteins penetrate the hydrophobic core of the lipid bilayer and have hydrophilic regions of amino acids when in contact with the aqueous environment. 63. List six major functions of membrane proteins. ○ Transport of specific solutes in/out the cell ○ Enzymatic activity, sometimes catalyzing one of a number of steps of a metabolic pathway ○ Signal transduction, relaying hormonal messages to the cell ○ Cell-to-cell recognition, allowing other proteins to attach two adjacent cells together ○ Intercellular joining of adjacent cells with a gap or tight junctions. ○ Attachment to the cytoskeleton and extracellular matrix, maintaining cell shape and stabilizing the location of certain membrane proteins 64. Define diffusion, passive transport, and active transport. Diffusion - is tendency of molecules of any substance to spread out in the available space Passive Transport Active Transport 65. Distinguish among hypertonic, hypotonic, and isotonic solutions. Hypertonic solutions have higher solute concentrations. Hypotonic solutions have lower solute concentrations. Isotonic solutions have equal solute concentrations. 66. Define osmosis and predict the direction of water movement based on differences in solute concentrations. Osmosis is the diffusion of water across a selectively permeable membrane. Water movement goes from hypotonic to hypertonic solution. When isotonic, the water moves at equal rates. 67. Describe how living cells with cell walls regulate water balance. Cells with cell walls osmoregulate to control water balance using the contractile vacuole to force water out of the cell. The cell wall keeps the cell from bursting, but cannot keep it from shrinking. 68. Distinguish among osmosis, simple diffusion, and facilitated diffusion. Facilitated diffusion is the passive movement of molecules down their concentration gradient vis transport proteins. Active transport requires the cell to expend metabolic energy (usually ATP) to enable the cell to maintain internal concentrations of small molecules that would otherwise diffuse across the membrane. 69. Explain how large molecules are transported across a cell membrane. Large molecules use vesicles to cross the membrane. The vesicle is moved by the cytoskeleton to the plasma membrane. When the two membranes come in contact, the bilayers fuse and split the contents to the outside 70. Distinguish between exocytosis, phagocytosis, pinocytosis and receptormediated endocytosis. Exocytosis is the release of contents outside of the cell. Endocytosis is the process of the cell taking in contents. Phagocytosis is cellular eating and pinocytosis is cellular drinking. Chapter 8 (An Introduction to Metabolism) 71. Distinguish between catabolic and anabolic pathways in cellular metabolism. Catabolic pathways release energy by breaking down complex molecules into simpler compounds. Anabolic pathways consume energy by building complicated molecules from simpler ones. 72. Explain why an organism is considered an open system. Organisms can exchange energy and matter with their surroundings. They have consume energy and release energy through CO2 and heat. 73. Explain the first and second laws of thermodynamics in your own words. Energy cannot be created or destroyed only transferred and transformed. During every energy transfer or transformation, some energy is unstable and often lost as heat. They also increase the entropy of the universe. 74. Distinguish between exergonic and endergonic reactions. Exergonic reactions releases energy which leads to a loss (negative) of spontaneous free energy. Endergonic reactions consume energy which leads to a gain of (positive) non spontaneous free energy. 75. List the three main kinds of cellular work. Chemical Work - pushing endergonic reactions such as the synthesis of polymers to monomers Transport Work - pumping of substances across a membrane against the direction of spontaneous movement Mechanical Work - such as contraction of muscle cells 76. Describe the structure of ATP. A ribose sugar, nitrogenous base adenine, and a chain of three phosphate groups. 77. Describe the function of enzymes in biological systems. 78. Explain how enzyme structure determines enzyme specificity. 79. Explain the induced-fit model of enzyme function. 80. What effects do the enzymes have on the activation energy of the reaction? 81. Explain how temperature, pH, and enzyme inhibitors can affect enzyme activity. Chapter 9 (Cellular Respiration: Harvesting Chemical Energy) 82. In general terms, distinguish between fermentation and cellular respiration. Fermentation and cellular respiration are both anaerobic. Cellular respiration requires oxygen but fermentation can be undergone without oxygen. 83. Write the summary equation for cellular respiration. C6H12O6 + 6 O2 → 6O2 + 6 H2O + Energy (ATP + Heat) Glucose + Oxygen → Carbon Dioxide + Water + Energy (ATP + Heat) 84. Define oxidation and reduction. Oxidation is the loss of electrons from one elements and reduction is the gain of electrons to another elements. 85. Describe what happens when NAD+ is reduced. What enzyme is involved? 86. In general terms, explain the role of the electron transport chain in cellular respiration. Breaks the fall of electrons to oxygen into several releasing steps 87. Name the three stages of cellular respiration and state the region of the eukaryotic cell where each stage occurs. Glycolysis - breaks down glucose into two molecules of pyruvate Citric Acid Cycle - completes the breakdown of glucose Oxidative Phosphorylation - accounts for most of the ATP synthesis 88. What stages of cellular respiration make ATP by substrate-level phosphorylation? Glycolysis and the citric acid cycle 89. List the products of the citric acid cycle. Explain why it is called a cycle. CO2, NADH, H+, FADH2. Its called a cycle because energy in the acetyl CoA drives reaction of acetate with oxaloacetate to produce citrate. 90. Explain oxidative phosphorylation in general terms, that is, how the exergonic “slide” of electrons down the electron transport chain is coupled to the endergonic production of ATP by chemiosmosis. Oxidative phosphorylation is a process that includes electron transport and chemiosmosis 91. Once NADH donates its electrons to the electron transport chain, what is the molecule that accepts these electrons at the end of this chain? In other words, what is the final electron acceptor in the electron transport chain 92. During cellular respiration, most of the energy flows in the following sequence: Glucose → → electron transport chain → → ATP. 93. Describe how food molecules other than glucose can be oxidized to make ATP. Each NADH and FADH2 molecule formed represents stored energy... contain high energy electrons from food molecules which are carried to an electron transport chain. Chapter 10 (Photosynthesis) 94. Distinguish between autotrophic and heterotrophic nutrition. 95. Describe the structure of a chloroplast, listing all membranes and compartments. A double membrane surrounding a dense fluid called the stroma and elaborate membrane system called thylakoids, enclosing the thylakoids space. 96. Write a summary equation for photosynthesis. 6 CO2 + 12 H2O + photons → C6H12O6 + 6 O2 (gas) (liquid) (aqueous) (gas) carbon dioxide + water + light energy → glucose + oxygen -CO2 reduced to glucose -H2O oxidized to O2 97. Describe the two main stages of photosynthesis in general terms. 98. List the wavelengths of light that are most effective for photosynthesis. 99. Explain what happens when chlorophyll a in an intact chloroplast absorbs photons. 100. List the components of a photosystem and explain the function of each component. 101. Trace the movement of electrons in the linear (noncyclic) electron flow. Linear electron flow is the primary pathway that involves both photosystem and produces ATP and NADPH using light energy. 102. Trace the movement of electrons in the cyclic electron flow. Cyclic electron flow only uses photosystem I and produces ATP, but not NADPH. No oxygen is released. 103. Explain the functions of the linear (noncyclic) and cyclic electron flow. 104. Describe the Calvin cycle in terms of what molecules get in and out of it. The Calvin cycle forms sugar from CO2 using ATP and NADPH. The cycle begins with carbon fixation incorporating CO2 into organic molecules 105. Describe the relationship between the light reactions and the Calvin cycle. The ATP provides the energy, and the NADPH supplies the electrons for the Calvin cycle, which converts carbon dioxide to sugar. The ADP and NADP+ that result from the Calvin cycle shuttle back to the light reactions, which regenerate ATP and NADPH. Chapter 12 (The Cell Cycle) 106. List the phases of the cell cycle and describe the sequence of events that occurs during each phase. ● Mitotic (M) phase includes mitosis and cytokinesis, and interphase, during which the cell grows and duplicates its chromosomes. ● Interphase, usually lasting 90% of the cell cycle, includes the G1 phase the first growing phase, the S phase is the DNA synthesis, and the G2 phase the 2nd gap that makes proteins to divide and gear up from mitosis. 107. List the phases of mitosis and describe the events characteristic of each phase. ○ Prophase - chromosomes condense and become visible. The nuclear membrane and nucleolus disappear . A spindle apparatus begins to form. In animal cells, centriole pairs move to either end of the spindle. The latter is prometaphase. ○ Metaphase - chromosomes align themselves in a plane which is perpendicular to the center of the spindle. This plane is called the metaphase plate. ○ Anaphase - sister chromatids split at the centromere and travel towards opposite ends of the spindle. Each chromatid is now considered a full chromosome ○ Telophase - chromosomes arrive at the ends of the spindle and the spindle apparatus begins to disassemble. New nuclear membranes are formed around the chromosomes uncoil. Cytokinesis begins as a cleavage furrow (in animal cell) or a cell plate (in plant cells) 108. Recognize the phases of mitosis from diagrams and micrographs. 109. Draw or describe the spindle apparatus, including centrosomes, kinetochore microtubules, nonkinetochore microtubules, asters, and centrioles (in animal cells). Centromeres - a narrow “waist” of the duplicated chromosome, where the two chromatids are most closely attached. It has two centrioles. Kinetochore - a structure of proteins attached to the centromere that links each sister chromatid to the mitotic spindle (prometaphase) Microtubules - a hollow rod that makes up part of the cytoskeleton in eukaryotic cells Nonkinetochore microtubules - overlap and push against each other, elongating the cell Asters - radial array of short microtubules that extends from each chromosome Centrioles - a structure in the centrosome of animal cells made of a cylinder of microtubule 110. Compare cytokinesis in animals and in plants. A cleavage furrow is formed in animal cell and a cell plate in plant cells 111. Distinguish among benign, malignant, and metastatic tumors. 112. Chapter 13 (Meiosis and Sexual Life Cycles) Explain in general terms how traits are transmitted from parents to offspring. Gametes transmit genes. During fertilization, male and female gametes unite, therefore passing on genes to the offspring. 113. Distinguish between asexual and sexual reproduction. Asexual reproduction is when an offspring can be produced by one parent, and they inherit the genetic information from that one parent. Sexual reproduction occurs when two parents produce an offspring and the offspring receive genetic information from both parents. 114. Distinguish between the following pairs of terms: a. somatic cell and gamete - The difference between somatic cells and gametes are somatic cells have a diploid number of chromosomes, gametes have a haploid (half) number b. autosome and sex chromosome - An autosome is any chromosome but the X and Y chromosomes. The Sex chromosomes are the X and Y chromosomes that distinguish he sex of the living things. 115. Explain how haploid and diploid cells differ from each other. State which cells in the human body are diploid and which are haploid. Haploid cells differ from Diploid cells because haploid have half the 46 chromosomes. Diploid has the full set. Only the sperm cells and cells in the ova are haploid cells. The body cells are mostly all Diploid. 116. Explain why fertilization and meiosis must alternate in all sexual life cycles. Meiosis maintains the normal diploid number by halving the number to make the gametes and then allowing the diploid number to be restored through fertilization 117. List the phases of meiosis I and meiosis II and describe the events characteristic of each phase. ○ Prophase I - chromosomes condense and become visible. The nuclear membrane and the nucleolus disappear and a spindle apparatus begins to form. Homologous chromosomes align during a process called synapsis. Crossing over (exchange of genetic material between homologous) occurs during this stage) ○ Metaphase I - chromosomes and their homologues align themselves in a plane which is perpendicular to the center of the spindle. This plane is called the metaphase plate. ○ Anaphase I - homologous chromosome pairs separate and each homologue travels towards opposite ends of the spindle ○ Telophase I & Cytokinesis - chromosomes arrive at the ends of the spindle and the spindle apparatus begins to disassemble. New nuclear membranes may be formed around the chromosomes. Cytokinesis may begin with a cleavage furrow or a cell plate. ○ Prophase II - the nuclear membrane and nucleolus, if present, may disappear. A spindle apparatus begins to form. ○ Metaphase II - chromosomes align themselves at the center of the spindle on the metaphase plate. ○ Anaphase II - sister chromatids split at the centromere and travel toward opposite ends of the spindle. Each chromatid is now considered a chromosome ○ Telophase II & Cytokinesis - chromosomes arrive at the ends of the spindle and the spindle apparatus begins to disassemble. New nuclear membranes are formed and the chromosomes uncoil. Cytokinesis begins 118. Recognize the phases of meiosis from diagrams or micrographs. 119. Describe the process of synapsis during prophase I and explain how genetic recombination (i.e. new genetic combination of the chromosomes) occurs. 120. Describe three events that occur during meiosis I but not during mitosis. 121. Explain how independent assortment, crossing over, and random fertilization contribute to genetic variation in sexually reproducing organisms. Chapter 14 (Mendel and the Gene Idea) 122. In Mendel’s monohybrid cross of pea plants with different flower colors, use the following figure to: a. label the P, F1, and F2 generations. b. Indicate the genotypes and phenotypes of the shown plants. c. Indicate the ratio of purple to white flower colored plants in each of F1 and F2 generations. 123. What is the difference between: a. An allele and a gene b. Homozygous and heterozygous individual for a particular gene. c. An organism’s phenotype and genotype. d. Monohybrid and dihybrid crosses. e. Complete dominance, incomplete dominance, and codominance. f. The law of segregation and the law of independent assortment. 124. What is a testcross? a. What is the purpose of a testcross? 125. A true-breeding purple (P) and tall (T) pea plant was hybridized with another true-breeding white (p) and dwarf (t) plant. Use this hybridization to answer the following questions. Show your work wherever there is any. 126. Define and give an example of: a. The genotypes of the parents. b. The genotypes of the gametes produced from the parents. c. The genotype and phenotype of the F1 generation. d. The genotypes of the gametes of F1 individuals before they self-pollinate. e. The Punnett square that shows the genotypes and phenotypes of F2 generation. f. The phenotypic ratios that result in the F2 generation. g. The probability of having the genotype PPtt in F2. h. The probability of having the genotype PpTt in F2 127. Chapter 15 (The Chromosomal Basis of Inheritance) What is the relationship between chromosomes, genes, and DNA? 128. What are linked genes? 129. What is a recombinant chromosome? 130. Red-green color blindness is caused by a sex-linked (X-linked) recessive allele. a. A man with normal vision marries a woman with normal vision whose father was color-blind. b. What is the probability that their daughter will be color-blind? c. What is the probability that their son will be color-blind? 131. What is the Barr body? 132. In what kind of human cells you’ll normally find a Barr body? 133. You have to know very well how nondisjunction in meiosis I causes a change in chromosomes # of gametes. You also have to know how to figure out the number of chromosomes in these gametes. 134. You have to know very well how nondisjunction in meiosis II causes a change in chromosomes # of gametes. You also have to know how to figure out the number of chromosomes in these gametes. 135. What is aneuploidy? 136. What are the alterations that might happen to a chromosomal structure? Chapter 16 (The Molecular Basis of Inheritance) 137. The DNA double helix has a uniform diameter because ________, which have two rings, always pair with ________, which have one ring. a. purines; pyrimidines d. pyrimidines; purines b. deoxyribose sugars; ribose sugars e. ribose sugars; deoxyribose sugars c. nucleotides; nucleoside triphosphates 138. What kind of chemical bond is found between paired bases of the DNA double helix? a. hydrogen b. ionic c. covalent d. sulfhydryl e. phosphate 139. Which of these is always true with regard to a DNA double helix? a. The amount of adenine is equal to the amount of uracil, and the amount of guanine is equal to the amount of cytosine. b. The amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of uracil. c. The amount of adenine is equal to the amount of guanine, and the amount of thymine is equal to the amount of cytosine. d. The amount of adenine is equal to the amount of cytosine, and the amount of guanine is equal to the amount of thymine. e. The amount of adenine is equal to the amount of thymine, and the amount of guanine is equal to the amount of cytosine. 140. The monomers of DNA and RNA are: a. amino acids. d. monosaccharides. b. nucleotides. e. fatty acids. c. nucleic acids. 141. Which of these is a difference between a DNA and an RNA molecule? a. DNA contains uracil, whereas RNA contains thymine. b. DNA is a polymer composed of nucleotides, whereas RNA is a polymer composed of nucleic acids. c. DNA is double-stranded, whereas RNA is single-stranded. d. DNA contains five-carbon sugars, whereas RNA contains six-carbon sugars. e. DNA contains nitrogenous bases, whereas RNA contains six-carbon sugars f. DNA contains nitrogenous bases, whereas RNA contains phosphate groups. 142. The strands that make up DNA are antiparallel. This means that ____________ a. DNA replication: b. occurs by the addition of nucleotides to the end of the DNA molecule. c. results in the formation of four new DNA strands. d. produces two daughter DNA molecules that are complementary to each other. e. uses each strand of a DNA molecule as a template for the creation of a new strand. f. 143. begins when two DNA molecules join together to exchange segments. When one DNA molecule is replicated to make two DNA molecules, the new DNA contains: a. occurs by the addition of nucleotides to the end of the DNA molecule. b. results in the formation of four new DNA strands. c. produces two daughter DNA molecules that are complementary to each other. d. uses each strand of a DNA molecule as a template for the creation of a new strand. e. begins when two DNA molecules join together to exchange segments. 144. When one DNA molecule is replicated to make two DNA molecules, the new DNA contains a. 25% of the parent DNA. d. 50% of the parent DNA. b. 75% of the parent DNA. e. 100% of the parent DNA. c. none of the parent DNA. Refer to the following list of enzymes and proteins to answer the following questions. The answers may be used once, more than once, or not at all. A. helicase B. nuclease C. ligase D. DNA polymerase E. primase F. single strand binding proteins 145. separates the DNA strands during replication ____________________________ 146. covalently connects segments of DNA ________________________________ 147. synthesizes short segments of RNA ________________________________ 148. DNA-cutting enzymes used in the repair of DNA damage ___________________ 149. removes the RNA nucleotides from the primer and adds equivalent DNA nucleotides to the 3' end of Okazaki fragments ___________________________ 150. catalyzes the elongation of a DNA strand in the 5' ( 3' direction by adding new 151. help to hold the DNA strands apart while they are being replicated ___________ 152. The leading and the lagging strands differ in that: a. the leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction. b. the leading strand is synthesized by adding nucleotides to the 3' end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5' end. c. the leading strand is synthesized continuously, whereas the lagging strand is d. synthesized in short fragments called Okazaki Fragments that are ultimately stitched together. e. both A and B f. 153. both A and C All of the following are functions of DNA polymerase in DNA replication except a. covalently adding nucleotides to the new strands. b. proofreading each added nucleotide for correct base pairing. c. replacing RNA primers with DNA. d. initiating a polynucleotide strand. e. none of the above 154. We would expect that a 15-nucleotide sequence will direct the production of a polypeptide that consists of a. 2 amino acids. d. 3 amino acids. b. 5 amino acids. e. amino acids. c. 15 amino acids. 155. Which one of the following is not a function of tRNA? a. joining to only one specific type of amino acid b. recognizing the appropriate codons in mRNA c. transferring nucleotides to rRNA d. helping to translate codons into amino acids e. All of the choices are functions of tRNA. Chapter 17 (From Gene to Protein) 156. What is a nucleotide? a. What are its components? 157. What is gene expression? 158. What are the two major stages of gene expression? 159. What is the one-gene one-polypeptide hypothesis? 160. What is the chain of command (i.e. the flow of information) to make a polypeptide (protein) from DNA? 161. What is transcription? 162. What are the nucleotide bases in DNA? _________ 163. How many types of amino acids are used to make proteins? ________ 164. How many DNA nucleotides make an order for one amino acid? ______ 165. How many mRNA nucleotides are translated into one amino acid? ___ a. What do you call this triplet of nucleotides? __________ 166. What is the enzyme that catalyzes RNA synthesis? ________ _________ 167. When RNA is being made, the RNA base A, U, C, OR G (CHOOSE ONE) always pairs with the base adenine (A) in DNA. 168. What is the first phase of transcription called? ____________________ 169. What is the name of the DNA sequence where RNA polymerase attaches to initiate transcription? _______________ 170. What is translation? 171. Where does translation take place in the cell? In the ________________ 172. What type of RNA transfers the amino acids to the ribosomes? _________ 173. Complete this sentence: The codon is a part of (m- or t-) RNA, while the anticodon is a part of (m- or t-) RNA. 174. How many subunits a ribosome has? _______ 175. How many binding sites for tRNA does the ribosome have? ________ 176. What are the three stages of translation? 177. When does termination of translation take place? 178. What is a mutation? 179. What is point mutation? 180. What are the possible consequences of a point mutation? 181. What are the two general categories of point mutation? 1. __________ 2. ________ 182. Define a base-pair substitution mutation? 183. Define the insertion and deletion mutations? 184. What are silent, nonsense, missense, and frameshift mutations? Practice the following mutations: What is the sequence of amino acids in the polypeptide translated form the following sequence of DNA: DNA strand 3’ T A C T T C A A A C C G A T T 5’ mRNA sequence 5’ 3’ amino acid sequence _____ - _____- _____ - _____ - _____ in the normal protein made from the above DNA sequence ______________________________________________________________________ An insertion of one base-pair (frameshift): A ↓ Original DNA strand 3’ T A C T T C A A A C C G A T T 5’ DNA strand after insertion of A 3’ T A C T T A C A A A C C G A T T 5’ mRNA sequence 5’ amino acid sequence 3’ _____ - _____- _____ - _____ - _____ in protein after a frameshift mutation. Here you have frameshift causing _____________ mutation. A deletion of one base-pair (frameshift): A ↑ Original DNA strand 3’ T A C T T C A A A C C G A T T 5’ DNA strand after deletion of A 3’ T A C T T C A A C C G A T T 5’ mRNA sequence 5’ amino acid sequence 3’ _____ - _____- _____ - _____ - _____in protein after a frameshift mutation. Here you have frameshift causing _____________ mutation.