AP Biology Unit 3 Chapters 8-10
1) Butterflies of the genus Colias live in the Rocky Mountains, where they experience a wide range of temperatures. Different variants of a particular glcolytic enzyme in the flight muscles are optimally active at different temperatures. Within the same population, some individual butterflies fly most effectively at 29˚C, while others fly most effectively at 40˚C. Still others can be equally active at both temperatures. Which of the following claims is most consistent with the observed butterfly behavior? A) Butterflies that express two variants of the enzyme are active over a greater range of temperatures B) Butterflies that are active at warmer temperatures produce more offspring C) Temperature has little effect on the activity of butterflies D) Butterflies that are active over a wide range of temperatures produce greater amounts of the enzyme
A
12) In addition to ATP, what are the end products of glycolysis? A) NADH and pyruvate B) CO2 and H2O C) CO2 and NADH D) CO2 and pyruvate E) H2O, FADH2, and citrate
A
16) As a research scientist, you measure the amount of ATP and NADPH consumed by the Calvin cycle in 1 hour. You find 30,000 molecules of ATP consumed, but only 20,000 molecules of NADPH. Where did the extra ATP molecules come from? A) cyclic electron flow B) photosystem I C) photosystem II D) linear electron flow E) chlorophyll
A
21) The figure above shows an organelle typically found in eukaryotic cells. Which of the following best describes the function of the double membrane system of this organelle? A) The inner membrane has specialized proteins that create a hydrogen ion concentration gradient between the inter-membrane space and the matrix B) The toxins and wastes entering a cell cross the outer membrane and are detoxified by digestive enzymes stored within the inter-membrane space C) The outer membrane contains transport proteins that establish a sodium ion concentration gradient used for ATP production, while the inner membrane contains transport proteins that establish a hydrogen ion concentration gradient used for glucose production D) The outer membrane allows the transport of all molecules into the inter-membrane space, while the inner membrane serves as the regulatory boundary
A
22) The energy required to run the Calvin cycle reactions of photosynthesis comes from which two substances produced during the light-dependent reactions? A) ATP and NADPH B) H+ and O2 C) H2O and CO2 D) O2 and CO2 E) ADP and PO4
A
23) An airtight, temperature-controlled glass box containing actively growing tomato plants was placed under a light source. Plastic wrapping that only transmits green light was placed over the box, and two days later air samples from inside the box were collected and analyzed. The most likely change in air quality is A) an increase in carbon dioxide (CO2) B) an increase in oxygen (O2) C) a decrease in carbon dioxide (CO2) D) an increase in nitrogen (N2) E) a decrease in nitrogen (N2)
A
25) Carbon dioxide (CO2) is released during which of the following stages of cellular respiration? A) oxidation of pyruvate to acetyl CoA and the Kreb's cycle B) fermentation and glycolysis C) glycolysis and oxidation of pyruvate to acetyl CoA D) the Kreb's cycle and oxidative phosphorylation E) oxidative phosphorylation and fermentation
A
29) The splitting of water to form oxygen gas occurs during A) photosynthesis B) both photosynthesis and respiration C) respiration D) neither photosynthesis nor respiration E) photo respiration
A
3) Which of the following are products of the light reactions of photosynthesis that are utilized in the Calvin cycle? A) ATP and NADPH B) electrons and H+ C) CO2 and glucose D) H2O and O2 E) ADP, Pi, and NADP+
A
6) Which of the following processes is carried out more efficiently by a C4 plant than by a C3 plant? A) Fixation of CO2 B) Transport of sugars C) light absorption D) Photosynthesis E) Chemiosmotic coupling
A
8) Which term most precisely describes the cellular process of breaking down large molecules into smaller ones? A) catabolism B) catalysis C) anabolism D) metabolism E) dehydration
A
11) Where are the molecules of the electron transport chain found in plant cells? A) stroma of chloroplasts B) thylakoid membranes of chloroplasts C) inner membrane of mitochondria D) cytoplasm E) matrix of mitochondria
B
18) Which of the following describes a metabolic consequence of a shortage of oxygen in muscle cells? A) No ATP production due to the absence of substrate-level phosphorylation B) A buildup of lactic acid in the muscle tissue due to fermentation C) An increase in blood pH due to the accumulation of lactic acid D) A decrease in the oxidation of fatty acids due to a shortage of ATP
B
19) According to the induced fit hypothesis of enzyme catalysis, which of the following is correct? A) The active site creates a micro environment ideal for the reaction B) The binding of the substrate changes the shape of the enzyme's active site C) Some enzymes change their structure when activators bind to the enzyme D) A competitive inhibitor can outcompete the substrate for the active site E) The binding of the substrate depends on the shape of the active site
B
24) A chemical reaction that has a positive ∆G is correctly described as A) endothermic B) endergonic C) exothermic D) spontaneous E) enthalpic
B
27) The pH of the inner thylakoid space has been measured, as have the pH of the stroma and of the cytosol of a particular plant cell. Which, if any, relationship would you expect to find? A) There is no consistent relationship B) The pH within the thylakoid is less than that of the stroma C) The pH of the thylakoid space is higher than that anywhere else in the cell D) The pH of the stroma is higher than that of the thylakoid space but lower than that of the cytosol E) The pH of the stroma is higher than that of the other two measurements
B
4) How can one increase the rate of a chemical reaction? A) Cool the reactants B) Add a catalyst C) Increase the entropy of the reactants D) Decrease the concentration of the reactants E) Increase the activation energy needed
B
5) Where is ATP synthase located in the mitochondrion? A) cytosol B) inner membrane C) mitochondrial matrix D) electron transport chain E) outer membrane
B
2) A plant has a unique photosynthetic pigment. The leaves of this plant appear to be reddish yellow. What wavelengths of visible light are being absorbed by this pigment? A) green, blue, and yellow B) blue, green, and red C) blue and violet D) green and yellow E) red and yellow
C
10) Trypsinogen is split by the enzyme enterokinase to form an activated molecule of the protease trypsin. Which of the following would confirm that the activation of trypsin is an example of how a positive feedback mechanism can amplify a biological process? A) The activated trypsin enzyme can use enterokinase as a substrate B) Each mRNA molecule that codes for trypsinogen can be translated repeatedly to form many peptide molecules C) The trypsin produced by the reaction is capable of splitting and activating additional trypsinogen molecules D) If levels of trypsin were to get too high, the trypsin molecules would inhibit the enzyme enterokinase
C
28) Which of the following questions will best direct an investigation of the mechanism of ATP Synthase? A) What is the source of the inorganic phosphate that is used to generate ATP from ADP? B) Can oxidative phosphorylation be uncoupled from the electron transport chain? C) Is the phosphorylation of ADP by ATP synthase dependent on the formation of a protein gradient? D) Can ATP synthase use the energy released by phosphorylation of ADP to pump protons against a concentration gradient?
C
30) Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes? A) the splitting of water B) the flow of electrons from photosystem II to photosystem I C) the synthesis of ATP D) the absorption of light energy by chlorophyll E) the reduction of NADP+
C
7) Increasing the substrate concentration in an enzymatic reaction could overcome which of the following? A) allosteric inhibition B) saturation of the enzyme activity C) insufficient cofactors D) denaturization of the enzyme E) competitive inhibition
C
13) Where does the Calvin cycle take place? A) cytoplasm surrounding the chloroplast B) outer membrane of the chloroplast C) chlorophyll molecule D) stroma of the chloroplast E) thylakoid membrane
D
14) If ATP breakdown (hydrolysis) is inhibited, which of the following types of movement across cell membranes is also inhibited? A) Movement of oxygen into a cell B) Facilitated diffusion of a permeable substance C) Movement of water through aquaporins D) Passage of a solute against its concentration gradient
D
17) Which of the following statements describes the results of this reaction? C6H12O6 + 6O2 —> 6CO2 + 6H2O + Energy A) CO2 is reduced and O2 is oxidized B) O2 is reduced and CO2 is oxidized C) O2 is oxidized and H2O is reduced D) C6H12O6 is oxidized and O2 is reduced E) C6H12O6 is reduced and CO2 is oxidized
D
15) When ATP releases some energy, it also releases inorganic phosphate. What purpose does this serve (if any) in the cell? A) It is released as an excretory waste B) It can be added to water and excreted as a liquid C) It can only be used to regenerate more ATP D) It can enter the nucleus to affect gene expression E) It can be added to other molecules in order to activate them
E
20) Reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction's A) heat content B) endothermic level] C) entropy D) free-energy content E) activation energy
E
26) Why are C4 plants able to photosynthesize with no apparent photorespiration? A) They conserve water more efficiently B) They do not participate in the Calvin cycle C) They exclude oxygen from their tissues D) the Kreb's cycle and oxidative phosphorylation E) oxidative phosphorylation and fermentation
E
9) In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of A) ATP, CO2, and lactate B) ATP, pyruvate, and acetyl CoA C) ATP, pyruvate, and oxygen D) ATP, NADH, and pyruvate E) ATP, CO2, and ethanol (ethyl alcohol)
E
