Studying for the AP Bio Midterm 2011 ANSWER KEY
Which of the following organelles is the site of cell respiration? • a. Golgi apparatusb. Chloroplastc. Mitochondria d. Endoplasmic reticulum • e. Ribosomes • 2. All of the following elements are found in a molecule of DNA EXCEPT • a. carbonb. phosphorusc. nitrogend. oxygen • sulfur • 3. A paleontologist comes across a preserved fossil of organic matter made up of cells that have ribosomes, a nucleus, an endoplasmic reticulum, a cell membrane and the remains of a cell wall, a Golgi apparatus and chloroplasts. This organic matter could have belonged to which of the following organisms? • a. a fungus • b. a virus • c. a bacterium • d. an animal • a plant • 4. The molecule that enters the Krebs cycle during the process of cell respiration is which of the following? • a. oxaloacetate • b. carbon dioxide • c. acetyl-CoA • d. citrate • e. RuBP
5. Which of the following macromolecules are polymers of glucose and act as storage polysaccharides in plants and animals? • a. Chitin and cellulose • b. Starch and glycogen • c. Cellulose and glycerol • d. Chitin and glucose • Cellulose and starch • 6. When water moves from liquid form to gas form, which of the following types of bonds is broken? • a. Covalent bonds • b. Polar covalent bonds • c. Ionic bonds • d. Hydrogen bonds • e. Van der Waals forces • 7. In photosynthesis, which of the following processes is the most direct result of the input of light energy from the sun? • a. The reduction of NADP • b. The creation of a proton gradient across the cristae. • c. The reduction of ADP • d. The functioning of ATP synthase • e. The excitation of electrons in photoystems I and II
8. The primary structure of proteins is made up of amino acids that are joined by which of the following types of bonds? • a. Ionic • b. Peptide • c. Double • d. Hydrogen • Disulfide • 9. In order to synthesize one molecule of glucose in photosynthesis, how many molecules of CO2 must enter the Calvin cycle? • a. One • B. Two • c. Three • d. Four • e. Six • 10. Which of the following is a catabolic (breakdown) process that occurs in the absence of oxygen and results in a partial degradation of sugar molecules? • a. Aerobic respiration • b. Oxidative phophorylation • c. Fermentation • d. The Calvin cycle • e. Noncyclic photophosphorylation
11. Enzymes speed up chemical reactions by doing which of the following? a. Increasing the number of substrate molecules available for reacting b. Lowering the activation energy of the reaction c. Changing the direction of the reaction d. Decreasing the G of the reactants e. Decreasing the G of the products 12. In oxidative phosphorylation, the final electron acceptor of the electron transport chain is which of the following? a. NAD+ b. NADPH c. Water d. Oxygen e. Carbon Dioxide 13. Which of the following can be found in both prokaryotic and eukaryotic cells? I. Ribosomes II. Nuclear Envelope III. Plasma Membrane IV. Cell wall V. Endoplasmic reticulum a. All of the above b. I, III, V c. I, III, IV d. I, II, III, IV e. II, III, IV
14. In proteins, disulfide bridges contribute to which of the following levels of structure? • a. Primary • b. Secondary • c. Tertiary • d. Quartenary • Induced fit • 15. In summer, the leaves of plants absorb which of the following colors least effectively? • a. Red • b. Blue • c. Violet • d. Green • Yellow • 16. Which of the following types of cells of the body would probably contain the most mitochondria? • a. Liver cells • b. Muscle cells • c. Neurons • d. Adipose (fat) tissue • e. Epidermal cells
17. Under a microscope, a biologist sees a cell engulfing food particles from the surrounding medium. The cell extends pseudopodia around the food, completely enclosing it and packaging it into a large sac. Which type of endocytosis is this? a. Pinocytosis b. Receptor-mediated endocytosis c. Phagocytosis d. Exocytosis e. Cotransport 18. Which of the following is not a correctly paired functional group? a. Hydroxyl – OH- b. Amine -NH2 c. Phosphate – PO4- d. Carbonyl- COOH e. Sulfhydryl- SH
19. During which of the following phases of the cell cycle is the cell’s DNA replicated? a. M phase b. S phase c. G1 phase d. G2 phase e. Cytokinesis 20. Glycolysis results in the net production of how many molecules of ATP? a. One b. Two c. Four d. Thirty two e.Thirty six 21. Carbon dioxide is produced during which stage of cell respiration? a. Glycolysis and the Krebs Cycle b. Stage 2 (oxidation of pyruvic acid) and the Krebs Cycle c. The electron transport chain and chemiosmosis d. The Calvin cycle e. Oxidative phosphorylation
Questions 22-24: Use the following list of choices (once, more than once or not at all) a. cholesterol b. glycoprotein (oligosaccharide) c. phospholipids bilayer d. extracellular matrix e. integral (intrinsic) protein 22. The membrane component that plays the most critical role in cell-to-cell signaling and recognition B 23. A steroid; it reduces the fluidity of membranes at moderate temperature A 24. Used for transport through the membrane during facilitated diffusion of ions or large macromolecules E
Questions 25-27, refer to the diagram below of a cross section of a plant leaf. • The most photosynthesis in the plant leaf occurs in these cells. B- palisades layer • Represents the vascular tissue of the plant leaf. E- xylem and phloem • 27. Represents the site of the most of the transpiration in a plant leaf. D- stomates A B C E D
28. The tendency of water molecules to stick together is known as a. adhesion b. cohesion c. surface tension d. hydration e. vaporization 29. Which of the following structures in plants is analogous to the cleavage furrow that appears during mitosis in animal cells? a. mitotic spindle b. kinetochore c. cell plate d. chromatids e. centrosome 30. All of the following processes are common to both eukaryotic mitosis and binary fission in bacteria EXCEPT a. duplication of the genetic material b. movement of the chromosome(s) toward opposite poles of the cell c. lining up of the chromosome(s) along the metaphase plate d. the formation of a new cell wall e. division of the cell cytoplasm
31. Fermentation, unlike oxidative phosphorylation (aerobic respiration) can occur in the absence of which of the following? a. water b. carbon dioxide c. NADH d. ATP e. oxygen 32. The only cells of the body that are NOT produced by the process of mitosis are a. cells of the brain b. bone marrow cells c. cells of the retina of the eye d. the gametes e. cells forming the epithelial lining 33. All of the following contribute to the fluidity of the cell membrane at normal, moderate temperature EXCEPT a. phospholipids lateral movement b. the presence of unsaturated fatty acid chains in the membrane phospholipids c. the movement of certain membrane-embedded proteins d. the presence of cholesterol molecules e. the ability of phospholipids to occasionally flip-flop
34. All of the following are true of both the process of chemiosmosis in plant cells during photosynthesis and cell respiration in animal cells EXCEPT a. they both take place across a membrane b. both processes include electron transport chains c. in both processes, the source of energy that initiates the electron transport chain is NADH d. in both processes, an H+ gradient is set up across the membrane e. in both processes, an H+ gradient drives the synthesis of ATP 35. The bonding of two glucose molecules to form maltose requires a. the release of a water molecule b. the addition of a water molecule c. the release of a carbon dioxide molecule d. the release of diatomic oxygen e. an input of ADP 36. Which of the following organelles is especially large and predominant in cells whose main function is to secrete, modify and package certain cell products? a. Endoplasmic reticulum b. Golgi apparatus c. Nucleus d. Ribosomes e. Vacuole
37. How is the energy of ATP used in photosynthesis? a. It is used to drive the electron transport chain in the light reactions. b. Its energy is used to split water in the thylakoids and release H+ to create the gradient used to drive oxidative phosphorylation. c. ATP drives the reactions that occur in the Calvin cycle. d. One of the phosphate groups is transferred to NADH to produce NADPH during the light reactions. e. The energy from it is used to create NADH from NAD+. 38. The first stable sugar, a three carbon molecule, produced by the Calvin cycle is a. acetyl-CoA b. glucose c. PGAL (G3P) d. rubisco e. RuBP 39. Plant cells, animal cells and bacteria all have which of the following in common? I. A large, central vacuole II. Ribosomes that can float free in the cytoplasm III. A membrane-bound nucleus a. I and II b. I only c. II only d. II and III only e. III only
40. Proteins are capable of carrying out all of the following functions in animals EXCEPT • a. coordinating the body’s activities through chemical messages • b. aiding in the transport of substances through the circulation • c. protecting the body from disease • d. aiding in muscle movement • e. storing energy for later use by the body • Questions 41-43 – Use the list below (once, more than once or not at all) • a. Cotransport • b. Active transport • c. Facilitated diffusion • d. Pinocytosis • e. Receptor mediated endocytosis • The sodium-potassium pump is an example of this type of transport. B • A non-specific form of endocytosis involving cellular drinking. D • 43. A form of passive transport that enables ionic molecules to cross the cell membrane. C 44. ATP drives a pump that concentrates a specific substance on one side of the membrane; this gradient drives the movement of another substance across the membrane. A
45. Which of the following is an example of simple diffusion across the phospholipid bilayer of a membrane? • a. The movement of H+ into the thylakoid space during photosynthesis • b. The uptake of neurotransmitters by the postsynaptic membrane during the transmission of a nerve impulse • c. The movement of oxygen in the alveoli across the epithelia membrane and into the bloodstream • d. The exchange of sodium and potassium across a cell membrane through the Na+/K+ pump • The movement of glucose across the body cell membranes and the cells of the liver, which stores it as glycogen • 46. The stomata-the openings on the underside surface of a plant leaf through which carbon dioxide is taken up and oxygen is expelled- are opened up as a result of • a. movement of mesophylls away from the stomatal opening • b increased turgidity in the guard cells • c. decreased turgidity in the guard cells • d. growth of the guard cells toward the mesophyll • e. elongation of the guard cells toward the mesophyll • 47. The region in the cell from which the mitotic spindles radiate out is called which of the following? • a. Centromere • b. Centrosome • c. Cytoplasm • d. Kinetochore • e. Metaphase plate
48. The lysosome has a high content of a. hydrolytic enzymes b. cytochromes c. DNA d. chlorophyll e. ribosomes
49. Which of the following would not increase the rate of transpiration in an angiosperm (flowering plant)? a. morning sunshine b. an increase in temperature from 20C to 30C c. an increase in relative humidity d. an increase in the water content of the soil e. an increase in air velocity
50. A fundamental difference between plants and animals concerns the ability to a. break down carbohydrates b fix CO2 into sugar c. adapt to appropriate environments d. carry on respiration e. resist diseases 51. The nucleolus is believed to function mainly in the a. provision of energy to the cell b. synthesis of ribosomes using rRNA and proteins c. synthesis of DNA d. secretion of enzymes e.manufacture of lipids 52. Which of the following is true about an enzyme? a. An enzyme is stable at high temperatures. b. An enzyme is a vitamin. c. An enzyme increases the activation energy of substrate and hence accelerates reactions. d. An enzyme catalyzes a reaction that is theoretically impossible otherwise e. An enzyme combines chemically with a substrate to form a temporary enzyme-substrate complex
53. By using the isotope O18 as a tracer element in studying photosynthesis. It has been possible to show that the O2 released in the process comes from a. O16 b. Sugar c. Carbon dioxide only d. Water only e. Carbon dioxide and water 54. Aerobic respiration and alcoholic fermentation are alike in all of the following ways EXCEPT: a. both release energy from glucose b. Acetaldehyde is converted into ethyl alcohol. c. ADP is changed to ATP. d. CO2 is a product e. NAD is reduced
Questions 55-57 – Use the list below (once, more than once or not at all • a. Hydrolysis • b. Phosphorylation • c. Glycolysis • d. Dehydration synthesis • e. Decarboxylation • 55. Reaction that converts ADP to ATP. B • 56. Reaction that converts fats to fatty acids and glycerol. A • 57. Reaction that converts glucose to pyruvic acid. C
58. Plant cells differ from animal cells in all of the following ways EXCEPT a. presence of cell walls b. presence of chloroplasts c. lack of centrioles d. lack of mitochondria e. none of the above 59. Which is produced in glycolysis? a. NADH b. FADH2 c. carbon dioxide e. ethanol f. H2O 60. In changes from warm to cold environments, ectotherms will a. shiver to generate heat b. actively cool the body by internal mechanisms c. maintain a constant body temperature d. Use hair or fur for extra insulation e. decrease respiratory rate
61. Facilitated diffusion: a. only transports solutes into the cell b. transports solutes passively down its concentration gradient c. requires ATP as its energy source d. is the cells’ only mechanism of movement e. is demonstrated by the sodium-potassium pump 62. CO2+H2O+light energy C6H12O6+O2+H2O summarizes which process in plants? a. oxidative phosphorylation b. fermentation c. photosynthesis d. citric acid (Krebs cycle) e. digestion 63. What is chitin? a. a contractile protein responsible for the movement of muscles, cilia, and flagella b. one of the ten essential amino acids c. a polysaccharide used by arthropods to form exoskeletons d. a precursor of steroid hormones e. the major component of plant cell walls that human cannot digest
64. Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants • a. the spindles contain cellulose microfibrils in addition to microtubules, whereas animal spindles do not contain microfibrils. • b. sister chromatids are identical, whereas in animals they differ from one another. • c. a cell plate begins to form at telophase, whereas in animals a cleavage furrow is initiated at that stage. • chromosomes become attached to the spindle at prophase, whereas in animals • chromosomes do not become attached until anaphase. • e. spindle poles contain centrioles, whereas spindle poles in animals do not. • 65. A common feature of starch and glycogen is that molecules of both • a. form microfibrils that give support to connective tissue fibers • b. contain repeated monomers of glucose and galactose • c. are important structural components of plant cell walls • d. are polymers of glucose • e. are water-soluble disaccharides • 66. Which of the following statements is true about the Krebs citric acid cycle and the Calvin (light independent) cycle? • a. They both result in a net production of ATP and NADH • b. They both require a net input of ATP • c. They both result in a release of oxygen • d. They both take place within the cytoplasmic matrix • e. They both are carried out by enzymes located within an organelle’s matrix.
67. The function of water in photosynthesis is to • a. combine with carbon dioxide • b. absorb light energy • c. supply electrons in the light-dependent reactions • d. transport H+ ions in the light-independent (dark) reactions • e. provide oxygen for the light-independent (dark) reactions • 68. When hydrogen ions are pumped out of the mitochondrial matrix, across the inner mitochondrial membrane, and into the space between the inner and outer membranes, the result is • a. damage to the mitochondrion • b. the reduction of NAD • c. the restoration of Na-K balance across the membrane • d. the creation of a proton gradient • e. the lowering of pH in the mitochondrial matrix
Questions 69-71- Use choices from the list below, once, more than once or not at all. • a. Centriole • b. Lysosome • c. Nucleolus • d. Peroxisome • e. Ribosome • 69. Contains catalase for the decomposition of hydrogen peroxide. D • 70. Assembles ribosomal precursors. C • 71. Contains hydrolytic enzymes associated with intracellular digestion of macromolecules. B
For questions 72-76, use the choices from the list below, once, more than once, or not at all. • a. Chemiosmosis • b. Electron Transport Chain • c. The Krebs Cycle • d. Glycolysis • e. Fermentation • The process by which glucose is split into pyruvate. D • The process by which a hydrogen gradient is used to create ATP. A • A process that regenerates NAD+ and can produce lactic acid as a product. E • A series of membrane embedded electron carriers that ultimately create the hydrogen ion gradient to drive the synthesis of ATP. B • 76. The process by which the carbon compounds are recycled as CO2 is produced. C
77. Mitosis in vertebrate cells occurs just after which of the following phases of the cell cycle? • a. G1 • b. S • c. DNA synthesis • d. G2 • e. M phase • 78. Which of the following statements best supports the idea that certain cell organelles are evolutionarily derived from symbiotic prokaryotes living in host cells? • a. The process of cell respiration in certain prokaryotes is similar to that occurring in mitochondria and chloroplasts. • b. Mitochondria and chloroplasts have linear DNA and tertiary proteins that are very similar to those in prokaryotes. • c. Mitochondria and prokaryotes have similar cell wall structure. • d. Like prokaryotes, mitochondria have a double membrane. • e. Mitochondria and chloroplasts have similar DNA and ribosomes to prokaryotes.
79. All of the following are results of hydrogen bonding EXCEPT • a. the high specific heat of water • b. the ability of some insects to walk on water • c. the polarity of the water molecule • d. the fact that solid water is less dense than liquid water • the relatively high boiling point of water. • 80. All of the following cell organelles are surrounded by phospholipid bilayer membranes EXCEPT • a. chloroplasts • b. nuclei • c. ribosomes • d. mitochondria • e. lysosomes
For Questions 81-83, use the choices listed below, once, more than once, or not at all. • a. Allosteric protein • b. Feedback inhibition • c. Competitive inhibitor • d. Noncompetitive inhibitor • e. Cofactor • 81. A molecule that looks similar to the normal substrate and competes for the active site of the enzyme to stop the reaction. • A molecule that binds to the enzyme at a site other than the active site, causing the enzyme to change shape and be unable to bind to the substrate. • 83. The process by which a metabolic pathway is shut off by the product it produces.
All of the following are types of wastes secreted by animals EXCEPTa. Ammoniab. Ureac.. Uric acidd. Carbon dioxidee. Nitrate • Consumption of CO2 can be used as a measure of photosynthetic rate because carbon dioxide is • a. Consumed during the light reactions • b. Consumed during the Calvin cycle of photosynthesis • c. Used to trap photons, the form of energy in sunlight. • d. Necessary for the production of ATP in oxidative phosphorylation • e. Produced when fermentation takes place. • 86. Which substances are components of the plasma membrane of a cell? • Glycoproteins b. Nucleic acids c. Ribozymes d. Phytochromes • e. Sodium ions
Which of the following can be viewed with a light microscope?a. Ribosome'sb. Golgi apparatusc. Nucleusd. Lipidse. Proteins • In photosynthesis, most ATP is produced as a result of which of the following processes? a. The Krebs citric acid cycle b. Carbon fixation c. The dark reactions d. The Calvin cycle e. Photolysis and the chemiosmosis of H+ ions through the thylakoids. • The movement of H+ ions down their concentrations gradient along the inner mitochondrial membrane through the ATP synthase during chemiosmosis of cellular respiration is an example of what type of movement across the membrane? a. Active transport b. Facilitated diffusion c. Cotransport d. Simple diffusion e. The work of an antiport
For questions 90-94, refer to the following diagram of the structure of a flower. • Develops into seeds after fertilization. G • The site of pollen production B • Receives pollen due to its sticky nature. A • Encloses and protects the flower prior to its opening. D • Structure that holds the anther up high and is part of the male stamen. H
For questions 95-98, refer to the following: A. Inner mitochondrial membrane (cristae) B. The cytosol C. Thylakoid membranes D. Ribosomes E. Nucleus • Where DNA is replicated prior to cell division. E • Where chlorophyll and carotenoids are located. C • The location of glycolysis. B • Where the enzyme catalase is first manufactured. D • How are steroid hormones able to cross cell membranes and enter cells? • a. Steroids and cell membranes both contain receptor proteins. • b. Steroids are polar, and the cell membrane is polar on the inside of the lipid bilayer. • c. Steroids are non-polar lipids, so they enter the cell via the phospholipid portion of the membrane by diffusion. • d. Steroids can diffusion through open channel proteins in the membrane. • e. Steroids move the cell membranes the same way water moves.
All of the following are functions of microtubules of the cell EXCEPTa. Components of cilia, used for locomotionb. Components of flagellum, used for locomotionc. Involvement in the movement of chromosomes during cell division.d. Components of the cytoskeleton to function in cell support.e. Part of the nuclear membrane. • Which of the following is the site of macromolecule hydrolysis in the cell? a. Mitochondria b. Centrosome c. Lysosome d. Golgi apparatus e. Ribosome • One way to best measure the metabolic rate of a cell would be to measure the rate at which a. Carbon dioxide is consumed by the cell b. Oxygen is consumed by the cell c. Water is consumed by the cell d. Oxygen is produced by the cell e. Glucose is produced by the cell • In certain plant cells, the synthesis of ATP occurs in which of the following a. Ribosomes and mitochondria b. Ribosomes and chloroplasts. c. Mitochondria and chloroplasts d. Mitochondria and the cytoplasm e. Chloroplasts and the cytoplasm
Refer to the diagram of the human digestivesystem for questions 104-108. • 104. This hormone release gastric juice to start the chemical digestion of proteins. I-stomach • This organ is the major site of chemical digestion. K-small intestines • Blood sugar levels are controlled by antagonistic hormones from this organ. • J-pancreas • Bile is produced here and glycogen is stored. E-liver • Peristalsis begins here. D-esophagus
The plasma membranes of winter wheat are able to remain fluid when it is extremely cold bya. Decreasing the number of cholesterol molecules presentb. Closing protein channelsc. Decreasing the number of hydrophobic proteins presentd. Replacing saturated fatty acids with unsaturated fatty acids.e. Using fatty acids with longer tails • Phagocytosis, pinocytosis and receptor-mediated endocytosis all involve a. the intake of large food molecules b. invagination of the plasma membrane c. the export of macromolecules d. the presence of receptor proteins e. the intake of fluids of the cell. • Which of the following is the driving force for facilitated diffusion? a. Concentration gradient b. ATP hydrolysis c. ADP hydrolysis d.. Phosphorylation e. GTPGDP exchange
The two sides of a membrane can be split apart from each other by an experimental technique known as freeze-fracturing. When one side of a free-fractured membrane is examined under the electron microscope, the exposed interior of the membrane bilayer appears to be covered with bumps. These bumps are most likelya. Integral membrane proteinsb. Ice crystalsc. Glycolipidsd. Organellese. vesicles • The component of a signal transduction pathway after the signal itself, is a(n) a. Responder b. Receptor c. Transducer d. Effector e. Cyclic Amp
Building blocks of proteins • a. A and C • b. B and H • c. B, F and I • d. C and D • e. B, E, F and I • One of the monomers of • carbohydrates • a. A b. B c. C • d. D e. E A. B. C. • The building blocks of nucleic • acids known as nucleotides • a. C and E • b. A and G • c. C and D • d. F and I • e. B and E D. E. F. G. H. I.
All of the following are true about the molecules seen below EXCEPT, • a. They are made of repeating units of amino acids • b. They have achieved the level of protein structure represented by the quaternary level. • c. They have different structures but similar functions. • d. Peptide bonds were used to create their basic primary structure. • e. Their structures are held together by hydrogen bonds, disulfide bridges, van der Waal forces and hydrophobic interactions.
Besides supplying the cell with ATP and NADH, the Krebs citric acid cyclea. breaks down glucoseb. produces ATP from NAD+c. uses oxygen in its cyclic reactionsd. converts lactic acid to pyruvic acide. makes carbon dioxide and FADH2 • Cyanide blocks the respiratory electron transport chain. As a result. a. the Krebs cycle speeds up. b. electrons and hydrogens cannot flow from NADH to oxygen. c. three ATPs are produced for every pair of electrons. d. production of water increases. e. glycolysis is inhibited. • Which one of the following is NOT associated with cold-blooded animals? a. Body temperature close to environmental temperature. b. Low metabolic rate at 10C. c. Insulating hair or feathers. d. Metabolic rate that varies with environmental temperature. e. Sluggish behavior in cold temperatures
During cyclic photophosphorylationa. Electron flow causes H+ ions to be transported into the thylakoidb. NADPH is produced.c. Water is split.d. Both photosystems I and II are involved.e. Oxygen is generated. • The dark reactions of photosynthesis take place within a. Membranes surrounding the chloroplast b. Thylakoids of the chloroplasts c. Cytoplasm outside the chloroplast d. Stroma of the chloroplast. e. Vacuole 123. All of the following take place in BOTH photosynthesis and respiration EXCEPT a. Electron flow b. Splitting of water c. Synthesis of ATP d. Transfer of electrons to carrier molecules e. Establishment of an H+ ion gradient
The normal air pathway in the human respiratory system isa. Trachea pharynx alveoli bronchib. Bronchi—> bronchiolepharynx tracheac. Alveoli bronchi bronchiolepharynxd. Trachea bronchialveoli pharynxe.Pharynx tranchea bronchi alveoli
A plant cell placed in a hypotonic environment willa. Lose water and become flaccidb. Actively transport salts out of the cellc. Take up water and burstd. Take up water and become turgide. Become impermeable to prevent water loss.
All of the following are functions of the mammalian kidney EXCEPTa. Removal of excess sodium loss from the blood.b. Reabsorption of salts and sugar from blood filtrate.c. Filtration of the bloodd. Concentration of urinee. Production of adrenaline
A response to changes in the length of the light is known asa.Photopheriodismb. Phototropismc. Photosynthesisd. Photoaxise. Photolysis • The oxygen in our atmosphere is a product of a. the splitting of carbon dioxide during photosynthesis b. cyclic photophosphorylation c. noncyclic photophosphorylation d. both cyclic and noncylic photophosphorylation e. the Calvin cycle • According to the current model of the sodium-potassium pump a. Na+ ions are pumped out of the cell and K+ ions are pumped in. b. hydrolysis of ATP is required. c. phosphorylation of the protein molecule d. all of the above.
130. A beet core is placed in a beaker filled with distilled water. If the pressure potential of the beet core is = -2 and the solute potential = -4. Using the formula you learned in your lab on diffusion and osmosis and your knowledge of biology to determine the water potential of both the distilled water and the beet core.a. Water potential in the beaker = 0; water potential in the beet core =0b. Water potential in the beaker = 0; water potential in the beet core =-0.2c. Water potential in the beaker = 0; water potential in the beet core = +0.2d. Water potential in the beaker cannot be calculated; water potential in the beet core = 0.2e. Water potential cannot be calculated; water potential in the beet core = -0.2 • Given the same example of the beet core in the distilled water as stated above, what would happen to the beet core cells after 24 hours? a. The beet core will lose water to the surrounding environment. b. The cells in the beet core are likely to undergo plasmolysis c. The beet core will likely gain so much water that its cells will rupture. d. The beet core cells would become turgid. e. The beet core cells will crenate and lyse.
132.Why don’t red blood cells pop in your bloodstreama. The blood provides an isotonic environment to your cells.b. The blood provides a hypotonic environment to your cells.c. The blood provides a hypertonic environment to your cells.d. Red blood cells are impermeable to water.e. Red blood cells have a wall that prevents them from popping. 133. Which bag would you predict to show the least change in mass at the end of the experiment? 3 4 5 1 2 • The bag in beaker 1 • The bag in beaker 2 • The bag in beaker 3 • The bag in beaker 4 • e. The bag in beaker 5
134. Which beaker(s) contain(s) a solution that is hypertonic to the bag? 1 2 3 4 5 • Beaker 3 • Beakers 2 and 4 • Beakers 1, 2 and 5 • Beaker 4 • e. Beakers 3 and 4 135. Using the same diagram shown above, arrange the beakers in order of the mass of the bags inside them after the experiment has run for 30 minutes. List the bag that loses the most mass first. a. 1,2, 3, 4, and 5 e. 2, 1, 5, 3 and 4 b. 1, 5, 2, 3, and 4 c. 4, 3, 2, 5 and 1 d. 3, 2, 1, 4 and 5
136. During what time interval is the enzyme working at its maximum velocity? • 0-30 seconds • 60-120 seconds • 120-180 seconds • d. Over the entire time course 137. In order to keep the rate constant over the entire time course, which of the following should be done? • Add more enzyme • Gradually increase the temperature after 60 seconds. • Add more substrate • d. Add sulfuric acid after 60 seconds.