Bio Exam 2 (ch. 3 & 6)

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While standing at the top of the stairs, you have a potential energy of 40 Joules. If you walk all the way down the stairs, what would your potential energy be at the bottom of the stairs? A. 0 Joules B. 20 Joules C. 40 Joules D. 80 Joules

A. 0 Joules

A nucleic acid containing 32% thymine would contain how much cytosine: A. 18% B. 32% C. 36% D. 64%

A. 18%

Starting with one molecule of acetyl CoA as an input, how many oxidation reactions occur during the Krebs cycle? A. 3 B. 6 C. 2 D. 1 E. 8

A. 3

Visible light has a wavelength range of: A. 400-740 nanometers. B. 200-400 nanometers. C. 0.001-100,000 nanometers. D. 200-800 nanometers. E. 200-740 nanometers.

A. 400-740 nanometers.

Under standard conditions, ATP can release _______ for every molecule converted to ADP. A. 7.3 Kcal of energy B. 1 to 2 cal of energy C. less than 1 cal of energy D. different amounts of energy depending on the cell

A. 7.3 Kcal of energy

When substrate-level phosphorylation occurs, it means that: A. ADP is converted into ATP by the addition of a phosphate group. B. NAD+ is converted into NADH. C. ATP is converted into ADP plus a phosphate group. D. NADH is converted into NAD+ plus a proton.

A. ADP is converted into ATP by the addition of a phosphate group.

Based on a variety of experiments, it is known that the rate of photosynthesis is highest when wavelengths of light between 400 and 500 nm are used, and when wavelengths around 700 nm are used. What can you infer about the relative importance of chlorophyll a and b in photosynthesis? A. Absorption of light by chlorophyll a and b is essential for the process of photosynthesis B. Reflection of light by chlorophyll a and b is essential for the process of photosynthesis C. Transmission of light by chlorophyll a and b is essential for the process of photosynthesis D. Chlorophyll a and b are much less important than other pigments in the reflection, absorption and transmission of light relevant to photosynthesis

A. Absorption of light by chlorophyll a and b is essential for the process of photosynthesis

Glucose is not our only food source, nor the only one we can utilize in our bodies to generate energy. Other primary sources of energy include other sugars, proteins, and fats. What metabolic intermediate are fats primarily converted into? A. Acetyl-CoA B. Pyruvate C. Krebs cycle intermediates D. ATP Synthase E. Electron transport chain components

A. Acetyl-CoA

In animals that take in oxygen from their environment, glucose is broken down into carbon dioxide and water in a process called: A. Aerobic respiration B. Organic compound respiration C. Glucose respiration D. Anaerobic respiration

A. Aerobic respiration

Many of the antiviral drugs currently used to treat HIV/AIDS also interfere with an enzyme that helps mitochondria multiply. Treatment can therefore result in a decrease in the number of mitochondria found in certain tissues. Given this information, what might you expect to see in patients treated with antiviral drugs? A. An increase in lactic acid levels B. An increase in oxidative phosphorylation C. An increase in phosphofructokinase activity D. An increase in NADH dehydrogenase activity

A. An increase in lactic acid levels

Most plants incorporate carbon dioxide into sugars by means of a cycle of reactions called the A. Calvin cycle. B. citric acid cycle. C. carbon cycle. D. CAM cycle. E. Krebs cycle.

A. Calvin cycle.

Macromolecules that are used by most organisms to store hereditary information are called: A. DNA molecules. B. ribosomal RNA molecules. C. proteins. D. transfer RNA molecules. E. messenger RNA molecules.

A. DNA molecules.

The equation for cellular respiration is: C6H12O6 + 6O2 6CO2 + 6H2O. At what specific point in the cellular respiration process has glucose been broken down completely from a six carbon molecule to 6 molecules of CO2? A. During the second oxidation in the Krebs cycle B. During pyruvate oxidation C. During the condensation reaction in the Krebs cycle D. During the priming reactions in glycolysis E. During the oxidation and ATP formation reactions in glycolysis

A. During the second oxidation in the Krebs cycle

The Law of Thermodynamics that states that energy cannot be created or destroyed is the A. First Law of Thermodynamics B. Third Law of Thermodynamics C. Second Law of Thermodynamics D. Fourth Law of Thermodynamics

A. First Law of Thermodynamics

This process is common to all living cells: A. Glycolysis B. Electron transport chain reactions C. Pyruvate oxidation D. The Krebs cycle E. Alcohol fermentation

A. Glycolysis

What aspect of cellular respiration occurs in the cytoplasm in eukaryotic cells? A. Glycolysis B. The Krebs cycle C. Pyruvate oxidation D. ATP synthesis E. The electron transport chain

A. Glycolysis

What is an end-product of glycolysis? A. Alcohol B. Oxaloacetate C. NAD+ D. ADP E. Pyruvate

E. Pyruvate

What stage of cellular respiration can occur in human cells with or without oxygen present? A. Glycolysis B. Pyruvate oxidation C. The Krebs cycle D. The electron transport chain

A. Glycolysis

What color of light is not strongly absorbed by chlorophyll? A. Green B. Red C. Violet-blue D. Yellow-orange

A. Green

Why may eating carrots be useful for enhancing vision? A. High levels of beta-carotene can lead to the production of a pigment used in vision. B. High levels of chlorophyll in carrots helps with photosynthesis in the eyes. C. High levels of NADPH in carrots can allow vertebrate eyes to perform the light reactions. D. High levels of carotenoids in carrots can allow vertebrate eyes to perform the dark reactions.

A. High levels of beta-carotene can lead to the production of a pigment used in vision.

CAM and C4 plants likely grow in what type of environment? A. Hot and arid B. In water C. Cool D. High altitude

A. Hot and arid

Margarine is made by hydrogenating vegetable oils so that they take on the consistency of butter. Propose a chemical basis for this change from a liquid to a solid. A. Hydrogenation of fats changes them from unsaturated to saturated, which are more solid. B. Hydrogenation of fats changes them from saturated to unsaturated, which are more solid. C. Trans fatty acids are changed from saturated to unsaturated, allowing them to solidify. D. Trans-fatty acids are changed from unsaturated to saturated, allowing them to solidify.

A. Hydrogenation of fats changes them from unsaturated to saturated, which are more solid.

phosphofructokinase is regulated by a number of factors, including high levels of ATP. Why is this enzyme regulated by ATP levels? A. If ATP levels are high, it is important to directly inhibit the reaction that commits the substrate to glycolysis to allow the substrate to be available for other reactions, since the cell has ample energy. B. If ATP levels are high, this provides a mechanism to directly inhibit the Krebs cycle, thus preventing further generation of NADH, FADH2 and ATP molecules that are not needed. C. If ATP levels are high, this provides a mechanism to directly inhibit the electron transport chain, thus preventing the formation of a proton gradient in the intermembrane space of mitochondria. D. If ATP levels are high, it is important to inhibit ATP synthase, and phosphofructokinase directly inhibits ATP synthase.

A. If ATP levels are high, it is important to directly inhibit the reaction that commits the substrate to glycolysis to allow the substrate to be available for other reactions, since the cell has ample energy.

A ribozyme catalyzes a reaction on itself and actually changes shape. This is an example of what? A. Intramolecular catalysis B. Intermolecular catalysis C. Inter-enzyme reactions D. Intra-enzyme reactions

A. Intramolecular catalysis

You are working with a specific enzyme-catalyzed reaction in the lab. You are a very careful experimentalist, and as a result, at the beginning of each of your experiments, you measure the temperature in the lab. On days 1 through 5, the temperature in the lab was 20oC. Today is day 6 of your experiment, and the temperature in the lab is 30oC. How do you predict that this will alter the rate of your enzyme-catalyzed reaction? A. It could possibly increase or decrease the rate. B. it will not affect the rate. C. It will increase the rate. D. It will decrease the rate.

A. It could possibly increase or decrease the rate.

In order to lose weight and reduce body fat, a friend of yours has decided to eliminate all fat from his diet, while consuming unrestricted amounts of carbohydrates. What do you think of this idea? A. It is a bad idea, because if ATP levels are high in cells, excess acetyl-CoA from the metabolism of carbohydrates can be used for fatty acid synthesis. B. It is a good idea, because under conditions where ATP levels are low in cells, carbohydrates will be stored, and fat stores will be catabolized via beta-oxidation to generate energy. C. It is a good idea, because if your friend doesn't eat any fat, he cannot store any additional fat. D. It is a bad idea, because consumption of fat is required to provide cofactors for the electron transport chain.

A. It is a bad idea, because if ATP levels are high in cells, excess acetyl-CoA from the metabolism of carbohydrates can be used for fatty acid synthesis.

What happens to the oxygen that is used in cellular respiration? A. It is reduced to form water B. It is used to make glucose C. It is converted to carbon dioxide D. It is used to make Krebs cycle intermediates E. It is converted to acetyl-CoA

A. It is reduced to form water

If you were able to increase the kinetic energy of the molecules inside your body, how would this affect your body temperature? A. It would increase. B. It would remain the same. C. It would decrease.

A. It would increase.

F. F. Blackman performed experiments to investigate the effects of various factors on photosynthesis. In one of his experiments, Blackman found that if light intensity was low that photosynthesis could be accelerated by increasing the amount of light, but not by increasing the temperature or carbon dioxide concentration. What can you conclude from this specific experiment? A. Light is important for photosynthesis B. Photosynthesis generates oxygen C. High temperatures are important for photosynthesis D. Carbon dioxide is important for photosynthesis

A. Light is important for photosynthesis

Carbonic anhydrase (CA), an enzyme widely present in plant and animal tissues, catalyzes the reaction: This reaction is important for the maintenance of acid base balance in blood and other tissues and to help transport CO2 out of tissues; without a catalyst, this reaction would not occur at rates that could maintain homeostasis. In the figure below, which line(s) represents the reaction catalyzed by carbonic anhydrase? A. Line B; the activation energy has been lowered. B. Line A; the activation energy increased. C. Lines A and B; product is shown for both lines. D. Line A; more energy is supplied. E. Either, as the free energy is the same for both.

A. Line B; the activation energy has been lowered.

If you exposed a C4 plant to 14CO2 in the light, which of the following would be the first organic molecule labeled with 14C? A. oxaloacetate B. pyruvate C. malate D. phosphoenolpyruvate (PEP)

A. oxaloacetate

What is different about the way that NADH and FADH2 donate electrons to the electron transport chain? A. NADH contributes its electrons to the first transmembrane complex in the electron transport chain and FADH2 contributes its electrons after the first transmembrane complex. B. The electrons from NADH ultimately go on to reduce oxygen to generate water, whereas the electrons from FADH2 are used to reduce pyruvate to lactate. C. NADH is oxidized and FADH2 is reduced. D. More protons are transported into the intermembrane space of the mitochondria in response to one molecule of FADH2 as compared to the number of protons transported in response to one molecule of NADH.

A. NADH contributes its electrons to the first transmembrane complex in the electron transport chain and FADH2 contributes its electrons after the first transmembrane complex.

In plants, the light-dependent reactions require A. NADP+. B. glucose. C. ATP. D. O2. E. Calvin cycle enzymes.

A. NADP+.

Tacrolimus (FK-506) is a drug that inhibits an enzyme called calcineurin. Calcineurin is a protein phosphatase. This is an enzyme that dephosphorylates (removes phosphate groups from) proteins. When added to cells, tacrolimus can inhibit the dephosphorylation of a protein called NFAT, but it cannot prevent the dephosphorylation of a protein called CDK1. What is the most likely explanation for this finding? A. NFAT is a substrate of calcineurin, but CDK1 is not. B. Tacrolimus changes the optimum pH for calcineurin. C. Tacrolimus is a competitive inhibitor of calcineurin for NFAT, but not for CDK1. D. Calcineurin requires an additional cofactor to dephosphorylate NFAT.

A. NFAT is a substrate of calcineurin, but CDK1 is not.

You eat a bowl of beans as part of your dinner. As you digest the beans, the proteins that are present get broken down to their component amino acids. As your body destroys the macromolecules that were present in the beans, is the energy present in those molecules destroyed? A. No. The energy contained within these macromolecules is converted into other forms of chemical energy and kinetic energy, though some is lost as heat. B. Yes. By breaking down these macromolecules, some of the energy they contained is destroyed. C. No. Breaking down molecules does not lead to the release of energy. D. No. While the vast majority of the energy contained in these macromolecules is converted to heat, it is not actually destroyed.

A. No. The energy contained within these macromolecules is converted into other forms of chemical energy and kinetic energy, though some is lost as heat.

The splitting of water and the generation of oxygen occur where? A. Photosystem II B. Photosystem I C. The Calvin Cycle D. The Krebs Cycle

A. Photosystem II

Jan Baptista van Helmont did an important experiment related to photosynthesis. He weighed a small willow tree and a pot of soil. Jan then planted the tree in the pot. Over the course of five years, he added only water to the pot. At the end of five years, he weighed the tree and found that it had gained 74.4 kg. He weighed the soil, and it was only 57 g less. What do the results of this specific experiment demonstrate about what is needed for a plant to grow and increase its mass? A. Plants must be able to increase their mass using substances in addition to what is found in soil. B. Plants need oxygen to grow. C. All of the food a plant needs to grow comes from the soil. D. Plants do not need soil to grow. E. All of the food a plant needs to grow comes from the water.

A. Plants must be able to increase their mass using substances in addition to what is found in soil.

You decide to go on vacation in the mountains, where you are staying in a cabin. Unfortunately, when you turn on the water in the cabin you smell hydrogen sulfide (H2S) gas. After some research, you find out that the H2S may be due to the presence of sulfur bacteria living in your pipes. What molecule do these bacteria use as an electron acceptor? A. SO4 B. H20 C. O2 D. H2S

A. SO4

If ATP synthase had a mutation in the F1 complex portion of the protein, what function of ATP synthase would most likely be affected? A. The conversion of ADP and Pi to ATP. B. The rotation of the rotor. C. The flow of protons through the channel. D. The insertion of the enzyme into the membrane.

A. The conversion of ADP and Pi to ATP.

As a forensic pathologist, you have just completed an autopsy of a poisoning victim. After a thorough examination, you conclude that the victim died of cyanide poisoning. You know that cyanide binds to the cytochrome oxidase complex, and therefore list the official cause of death as suffocation due to cyanide exposure. However, if you wanted to provide a more technical explanation as to the cause of death, what process was specifically inhibited directly by cyanide? A. The formation of water from oxygen B. All proton pumping into the intermembrane space C. ATP synthesis D. The oxidation of FADH2 E. The reduction of NAD+

A. The formation of water from oxygen

Arsenic poisoning can lead to organ failure and death. Though arsenic can inhibit or interfere with a number of cellular enzymes, arsenic poisoning is thought to be mainly due to indirect inhibition of enzymes involved in both pyruvate oxidation and the Krebs cycle. As a result, this compound must be able to enter what cellular compartment? A. The mitochondrial matrix B. The cytoplasm C. The endoplasmic reticulum D. The intermembrane space of the mitochondria E. The nucleus

A. The mitochondrial matrix

As electrons travel from the primary electron acceptor in photosystem II, down the electron transport chain to photosystem I, they drive the movement of protons from the stroma into the thylakoid compartment. Why is the development of this chemical gradient useful to photosynthesis? A. The proton gradient can drive the production of ATP, which is needed for the light-independent reactions B. Protons are directly used in the thylakoid to make glucose C. This proton gradient is used to make NADPH, which is needed for the Calvin cycle D. Protons provide the energy needed to drive the light-dependent reactions

A. The proton gradient can drive the production of ATP, which is needed for the light-independent reactions

What is common to all of the oxidation reactions in the Krebs cycle? A. They are all characterized by a loss of electrons from an organic molecule coupled to the reduction of an electron acceptor. B. They are all decarboxylation reactions. C. They all lead to the generation of NADH. D. They all lead to substrate-level phosphorylation of ADP to generate ATP.

A. They are all characterized by a loss of electrons from an organic molecule coupled to the reduction of an electron acceptor.

What must happen to amino acids before they can be used in catabolic reactions? A. They must be deaminated. B. They must be decarboxylated. C. They must be deoxygenated. D. They must be dehydrogenated.

A. They must be deaminated.

In aerobic respiration, chemiosmotic generation of ATP is driven by: A. a difference in H+ concentration on the two sides of the inner mitochondrial membrane. B. large quantities of ADP. C. the Na+/K+ pump. D. osmosis of macromolecules. E. Pi transfer through the plasma membrane.

A. a difference in H+ concentration on the two sides of the inner mitochondrial membrane.

Glucose is converted into glucose 6-phosphate by hexokinase. Glucose 6-phosphate then serves as the substrate for the enzyme phosphoglucose isomerase, which converts this reactant into fructose 6-phosphate. Fructose 6-phosphate serves as the substrate for phosphofructokinase, which converts fructose 6-phosphate into fructose 1,6-bisphosphate. Based on the information provided, this is an example of A. a metabolic pathway. B. allosteric regulation. C. enzyme inhibition. D. feedback inhibition.

A. a metabolic pathway.

Carotenoids are important to many plants because these pigments are able to A. absorb wavelengths of light that neither chlorophyll a nor b can absorb. B. remove carbon dioxide from the air. C. store electrons for use during the "dark" reaction of photosynthesis. D. capture UV radiation that is harmful to the DNA in the nucleus of plant cells. E. absorb water so that hydrolysis can be carried out in the chloroplasts.

A. absorb wavelengths of light that neither chlorophyll a nor b can absorb.

Relatively small organic molecules with a central carbon atom which is bonded to a carboxyl group, an amino group, a carbon containing group, and a hydrogen atom are called: A. amino acids. B. fatty acids. C. enzymes. D. peptides. E. nucleotides.

A. amino acids.

In photosynthesis, ATP is made by A. chemiosmosis. B. the passing of electrons from photosystem I to an electron transport chain. C. the Calvin cycle. D. the Krebs cycle. E. glycolysis.

A. chemiosmosis.

A modified form of cellulose found in the exoskeletons of insects and crustaceans is known as: A. chitin B. starch C. amylose D. glycogen

A. chitin

The organic non-protein components that aid in enzyme functioning are called A. coenzymes. B. products. C. cofactors. D. substrates. E. reactants.

A. coenzymes.

A drug binds to the active site of an enzyme. If it is bound to the active site of the enzyme, it prevents substrate binding. This drug would be considered a A. competitive inhibitor. B. allosteric activator. C. noncompetitive inhibitor. D. allosteric inhibitor.

A. competitive inhibitor.

The light-independent reactions of photosynthesis are those that A. convert CO2 into reduced molecules (sugars). B. convert glucose into energy. C. occur only at night. D. convert water into hydrogen and oxygen. E. convert chlorophylls into light energy.

A. convert CO2 into reduced molecules (sugars).

For a particular chemical reaction, the enthalpy of the reactants is -400 kJ. The enthalpy of the products is -390 kJ. The entropy of the reactants is 0.2 kJ/K. The entropy of the products is 0.3 kJ/K. The temperature of the reaction is 25oC. The likely conclusion you can draw from this reaction is it is A. exergonic. B. endergonic. C. a redox reaction. D. being catalyzed by an enzyme.

A. exergonic.

If the gene encoding the enzyme rubisco is mutated such that it is non-functional, the process that would be affected is the ability to A. fix carbon. B. make O2. C. harvest photons. D. make ATP. E. make NADPH.

A. fix carbon.

The amount of energy available to do work is called A. free energy. B. kinetic energy. C. potential energy. D. activation energy.

A. free energy.

Glucose is broken down through cellular respiration, which involves a large number of chemical reactions. At the end of the cellular respiration process, a large number of ATP molecules are generated, yet not all of the possible energy that is contained in a molecule of glucose can be harnessed through these chemical reactions to generate ATP. In other words, during cellular respiration, not all of the energy that is contained in a molecule of glucose is converted into the energy stored in ATP. The remaining energy is A. lost as heat. B. donated to molecules in the cellular respiration process to reduce them. C. destroyed. D. used to drive exergonic reactions.

A. lost as heat.

During the light-dependent reactions, due to electron transport, the thylakoid space becomes A. more acidic than the stroma. B. the site where the Calvin cycle occurs. C. the site of NADPH production. D. the site of ATP synthesis.

A. more acidic than the stroma.

Chitin, a modified form of cellulose, is not only cross-linked with proteins but its glucose units are modified with atoms of: A. nitrogen. B. hydrogen. C. oxygen. D. sulfur. E. phosphorous.

A. nitrogen.

Benedict's reagent is a chemical that is used as a test for the presence of a free aldehyde functional group on glucose. The aldehyde is used when glucose and fructose bind together to form sucrose, and the Benedict's test is negative. Starch contains a great deal of glucose but gives a negative Benedict's test because: A. only the glucose at the end of a chain of starch will have an exposed aldehyde functional group to react with Benedict's reagent. B. starch is not soluble in water and cannot react with Benedict's reagent. C. all of the aldehyde groups on the starch are oxidized and cannot react with the Benedict's reagent. D. glucose in starch has lost a carbon atom and cannot react with Benedict's reagent.

A. only the glucose at the end of a chain of starch will have an exposed aldehyde functional group to react with Benedict's reagent.

The types of bonds linking nucleotides in nucleic acids are: A. phosphodiester bonds. B. peptide bonds. C. ionic bonds. D. non-polar covalent bonds.

A. phosphodiester bonds.

A polymer with the sequence 5' ACGTACGAATAG 3' is a: A. piece of DNA. B. piece of RNA. C. protein. D. polysaccharide.

A. piece of DNA.

The specific amino acid sequence of a protein is its ____. A. primary structure B. secondary structure C. tertiary structure D. quaternary structure

A. primary structure

In which part of the chloroplasts are the Calvin cycle enzymes located? A. stroma B. thylakoids C. grana D. envelope E. cristae

A. stroma

This type of lipid is found in pigments such as chlorophyll, in the visual pigment retinal, and in rubber: A. terpene. B. prostaglandin. C. phospholipid. D. steroid. E. wax.

A. terpene.

If the G of a reaction was -31.45 kJoules, you would know that A. the reaction is spontaneous. B. the products have more free energy than the reactants. C. the reaction requires an energy input of 31.45 kJoules to proceed. D. the reaction most likely leads to development of a more ordered system.

A. the reaction is spontaneous.

A nucleic acid contains thymine, allowing you to conclude that: A. this nucleic acid is DNA. B. this nucleic acid is RNA. C. this nucleic acid could be either DNA or RNA.

A. this nucleic acid is DNA.

Which reaction illustrates a dehydration reaction? A)) A + H2O -> B + C B)) A + B -> C + H2O C)) A -> B + C+ H2O D)) A + B + H2O -> C

B)) A + B -> C + H2O

In the reaction: C4H6O4 + FAD C4H4O4 + FADH2, what type of reaction took place to remove the protons from C4H6O4? A. Oxidation B. Dehydrogenation C. Reduction D. Decarboxylation

B. Dehydrogenation

What would be the ATP yield for a molecule that is catabolized to form one molecule of pyruvate in a eukaryotic cell? A. 10 ATP B. 12.5 ATP C. 25 ATP D. 30 ATP E. 32 ATP

B. 12.5 ATP

A plant researcher wants to construct a synthetic cellulose fiber from 20 glucose molecules. How many molecules of CO2 and glyceraldehyde-3-phosphate are needed to construct the fiber? A. 120, 120 B. 120, 40 C. 20, 40 D. 120, 60 E. 20, 60

B. 120, 40

What is the net number of ATP generated directly during glycolysis per molecule of glucose? A. 0 B. 2 C. 4 D. 6 E. 8

B. 2

What are the products of one turn of the Krebs cycle? A. 1 CO2, 2 NADH, 1 FADH2, 1 ATP B. 2 CO2, 3 NADH, 1 FADH2, 1 ATP C. 4 CO2, 12 NADH, 4 FADH2, 4 ATP D. 4 CO2, 6 NADH, 2 FADH2, 2 ATP E. 2 CO2, 6 NADH, 2 FADH2, 2 ATP

B. 2 CO2, 3 NADH, 1 FADH2, 1 ATP

The DNA sequence capable of pairing with 5' CGATTAGT 3' is: A. 5' GCTAATCA 3' B. 3' GCTAATCA 5' C. 3' CGATTAGT 5' D. 5' CGATTAGT 3'

B. 3' GCTAATCA 5' G-C, T-A

If you take into account the amount of ATP generated by ATP synthase per molecule of NADH produced in aerobic respiration, the net number of ATP molecules produced by substrate-level phosphorylation, and the fact that NADH molecules produced in the cytoplasm have to be transported into the mitochondria, what is the predicted energy yield of glycolysis in eukaryotic cells? A. 32 ATP B. 5 ATP C. 30 ATP D. 7 ATP E. 2 ATP

B. 5 ATP

Starting with one molecule of glucose as an input, how many oxidation reactions occur during the Krebs cycle? A. 3 B. 6 C. 2 D. 8 E. 1

B. 6

Hemoglobin transports oxygen in the blood and consists of a chain of 146 amino acids. If amino acids were incorporated into hemoglobin in the same proportions, approximately how many alanine residues would you predict to find in hemoglobin? A. 2 B. 7 C. 20 D. 36 E. 146

B. 7

The normal body temperature of a bat is similar to the normal body temperature of a human. Which of the curves below most likely represents an enzyme from a bat? A. C B. A C. B

B. A

Why is the energy generated from the catabolism of sugars and other macromolecules ultimately harnessed to generate ATP? A. ATP is required to generate the proton gradient in the intermembrane space of mitochondria. B. ATP can be used by cells to drive endergonic reactions. C. ATP synthesis is an exergonic reaction. D. ATP can be used to make RNA, which is an energy storage molecule in the cell.

B. ATP can be used by cells to drive endergonic reactions.

What important metabolic intermediate does not cross the inner membrane of the mitochondria? A. ATP B. Acetyl-CoA C. Oxygen D. Pyruvate

B. Acetyl-CoA

Acyclovir is an antiviral chemical that resembles a nucleotide but lacks a 3' OH group and cannot form phosphodiester bonds. Why is Acyclovir useful in treating some viral infections? A. Acyclovir stops viral protein synthesis. B. Acyclovir halts viral DNA replication. C. Acyclovir blocks the assembly of viral cell capsules. D. Acyclovir hydrolyzes viral polysaccharides.

B. Acyclovir halts viral DNA replication.

A human cell has a mutation in the gene that encodes the enzyme that generates lactate from pyruvate, rendering that enzyme completely non-functional. Assuming that there is ample glucose present, how would this cell generate energy in the presence of oxygen? A. This cell would have no way to generate energy under these conditions because it cannot carry out the reactions needed for glycolysis. B. Aerobic respiration. C. Primarily through the break down of proteins into amino acids. D. Glycolysis coupled with ethanol fermentation.

B. Aerobic respiration.

The ATP generated from cellular respiration is not sufficient to drive the Calvin cycle in plants, even if appropriate levels of NADPH and CO2 are present. Why not? A. Cellular respiration and photosynthesis do not happen in the same cells in plants. B. Breaking down sugar to provide the energy needed to synthesize sugar would be a futile cycle. C. Plants do not undergo cellular respiration. D. The Calvin cycle requires more ATP than can possibly be made from cellular respiration.

B. Breaking down sugar to provide the energy needed to synthesize sugar would be a futile cycle.

Many types of cancer cells have been detected to secrete significant levels of lactate. Do you think these cells are likely undergoing beta-oxidation? A. No, because lactate is consumed in beta-oxidation. B. No, because if lactate is being produced, the cell is not likely making use of the pathways needed to make use of the products of beta-oxidation. C. Yes, because lactate stimulates beta-oxidation. D. Yes, because beta-oxidation can generate intermediates that would lead to the production of lactate.

B. No, because if lactate is being produced, the cell is not likely making use of the pathways needed to make use of the products of beta-oxidation.

AMP-activated protein kinase (AMPK) is an enzyme that is activated by high levels of AMP in cells. If levels of AMP are high in cells, that means that levels of ATP are low. Once active, AMPK activates catabolic pathways and inhibits anabolic pathways in the cell. Why do you think that is the case? Choose the answer that best explains the role of AMPK. A. High levels of AMP indicate that there is a high amount of energy stored in the cell, thus activating catabolic pathways and inhibiting anabolic pathways are mechanisms to use stored energy. B. By activating catabolic pathways, AMPK provides a mechanism to activate exergonic pathways, which is important if AMP levels are high in the cell. C. Activating catabolic pathways and inhibiting anabolic pathways will ultimately lead to higher consumption of ATP, which is important if AMP levels are high in the cell. D. By inhibiting anabolic pathways, AMPK provides a mechanism to generate heat for the cell, which is important if AMP levels are high in the cell.

B. By activating catabolic pathways, AMPK provides a mechanism to activate exergonic pathways, which is important if AMP levels are high in the cell.

You have recently identified a novel protein and obtained its sequence. How could you use this sequence to predict the function of the protein? A. By determining the secondary structure of the protein. B. By looking for conserved domains. C. By using the sequence to make antibodies against the protein. D. By determining the DNA sequence that could encode the protein.

B. By looking for conserved domains.

Which type of plant can utilize the Calvin cycle? A. C4 plants B. C3, C4, and CAM plants C. CAM plants D. C3 plants

B. C3, C4, and CAM plants

A phosphorus shortage in soil would make it difficult for plants to produce: A. amylose B. DNA C. cellulose D. starch

B. DNA

You are studying an enzyme-catalyzed reaction that induces a particular cellular activity in the lab. If you wanted to slow down that particular cellular activity by controlling the enzyme, what could you do? A. Add an allosteric activator to the cells. B. Decrease the temperature of the incubator where the cells are growing. C. Add cofactors to the media the cells are growing in. D. Increase the pH of the media the cells are growing in to the optimum pH.

B. Decrease the temperature of the incubator where the cells are growing.

As a result of the transition from daytime to nighttime, how will the relative concentrations of glyceraldehyde 3-phosphate (G3P) and ribulose 1,5-bisphosphate (RuBP) change in C3 plants? A. G3P would decrease and RuBP would increase. B. G3P would increase and RuBP would decrease. C. The concentrations of G3P and RuBP would remain the same. D. The concentrations of G3P and RuBP would both decrease.

B. G3P would increase and RuBP would decrease.

If citrate levels are high in the cell, but ATP levels are low, what do you think will happen in the cell? A. Glycolysis and the Krebs cycle will both be inhibited, thus under these conditions there will be no mechanism to generate ATP. B. Glycolysis will be inhibited, but the Krebs cycle will be functional, allowing it to be utilized to breakdown acetyl-CoA generated from beta-oxidation. C. In the presence of glucose, glycolysis will run to generate energy for the cell, but the Krebs cycle will be inhibited. D. The electron transport chain will be inhibited, causing a build-up of NADH and FADH2. This will inhibit the Krebs cycle, but in the presence of glucose, glycolysis will still run coupled with fermentation to regenerate NAD+.

B. Glycolysis will be inhibited, but the Krebs cycle will be functional, allowing it to be utilized to breakdown acetyl-CoA generated from beta-oxidation.

Organisms that depend on the energy stored in chemical bonds by other organisms for their food energy are called ____________. A. Oligotrophs B. Heterotrophs C. Chemotrophs D. Autotrophs

B. Heterotrophs

What is the difference in the bonding between alpha-helix and beta sheets? A. Hydrogen bonding between the amides only occurs in one of these two types of secondary structures. B. Hydrogen bonding occurs between the amides of adjacent chains in the sheets instead of between the amides in different parts of the helices. C. Sulfur bridges allow the spring like turns in alpha helices and van der Waals dispersion allows the folds in beta sheets. D. Hydrogen bonding always occurs in the alpha helices but only occurs in parallel beta sheets.

B. Hydrogen bonding occurs between the amides of adjacent chains in the sheets instead of between the amides in different parts of the helices.

Where does pyruvate oxidation occur in eukaryotic cells? A. In the nucleus B. In the mitochondria C. In the Golgi body D. In the cytoplasm E. In the plasma membrane

B. In the mitochondria

In a chemical reaction, glyceraldehyde-3-phosphate + NAD+ yields 1,3-bisphosphoglycerate + NADH. In this reaction, what happened to NAD+? A. It served as an enzyme to catalyze the reaction, and at the end of the reaction formed NADH B. It was reduced to form NADH C. It was activated to form NADH D. It was oxidized to form NADH

B. It was reduced to form NADH

What are the characteristics of red light, which is absorbed by chlorophylls? A. It is not considered a part of the visual spectrum B. Its photons have the longest wavelength in the visual spectrum C. Its photons have the highest energy in the visual spectrum D. Its photons have the shortest wavelength in the visual spectrum

B. Its photons have the longest wavelength in the visual spectrum

The aquatic plant Elodea is commonly used to study photosynthesis. You put some Elodea in a test tube filled with water containing radiolabeled oxygen (18O), shine light on the test tube, and measure the rate of photosynthesis by counting oxygen bubbles released. At the end of your experiment, you would find the most 18O in A. in ATP. B. O2. C. carbon dioxide. D. glucose. E. in water for the most part, as water is not used in photosynthesis.

B. O2

In the photosystem I reaction center of green plants, light energy captured by pigment molecules is passed to a special reaction center chlorophyll a called A. P870. B. P700. C. chlorophyll I. D. chlorophyll II. E. P680.

B. P700.

You label cells with a radioactive isotope of sulfur (35S). The only molecules that would be radioactively labeled in these cells are: A. Carbohydrates B. Proteins C. Nucleic acids D. Lipids

B. Proteins

In glycolysis, a major portion of the energy remains in the final product, which is called: A. Glyceraldehyde 3-phosphate (G3P) B. Pyruvate C. Glucose D. Citrate

B. Pyruvate

When amino acids are degraded in cells, into what intermediate(s) of the aerobic respiration process are the carbon skeletons of amino acids primarily converted? A. Pyruvate B. Pyruvate and Krebs cycle intermediates C. Acetyl-CoA D. Krebs cycle intermediates E. Pyruvate and acetyl-CoA

B. Pyruvate and Krebs cycle intermediates

Which amino acid is most soluble in water? A. Leucine B. Serine C. Glycine D. Valine

B. Serine

You discover a new organism while on vacation in Yellowstone Park. You use a series of experiments to establish that it carries out aerobic respiration, but find that it has a unique ATP synthase that requires 16 protons per rotation. What does this tell you about the P/O ratio in this organism? A. The new organism only makes ATP by substrate-level phosphorylation B. The P/O ratio in the new organism is lower than your P/O ratio C. The P/O ratio in the new organism is the same as your P/O ratio D. The P/O ratio in the new organism is higher than your P/O ratio

B. The P/O ratio in the new organism is lower than your P/O ratio

What characteristic would the R groups of amino acids have if they are located within the interior of biological membranes? A. The R groups would be polar. B. The R groups would hydrophobic. C. The R groups would be hydrophilic. D. The R groups would be able to form ionic bonds.

B. The R groups would hydrophobic.

A new antibiotic has been developed that inhibits the activity of an enzyme by competitive inhibition. What effect will this have on the activation energy of the enzyme-catalyzed reaction? A. The activation energy required for the reaction in the presence of the antibiotic would be less than the activation energy required in the absence of the antibiotic. B. The activation energy required for the reaction in the presence of the antibiotic will be the same as the activation energy required in the absence of the antibiotic. C. The activation energy required for the reaction in the presence of the antibiotic would be greater than the activation energy required in the absence of the antibiotic.

B. The activation energy required for the reaction in the presence of the antibiotic will be the same as the activation energy required in the absence of the antibiotic.

Many metabolic pathways are ultimately concerned with ATP; either with the generation of ATP, or with the requirement of ATP for that pathway to function. Why is ATP so important to metabolism? A. ATP is a protein that serves as the energy currency of cells. B. The phosphate groups of ATP are held together by unstable bonds that can be broken to release energy. C. Hydrolysis of the bond between adenine and ribose in ATP is commonly used to release energy that can be used to drive other cellular reactions. D. Hydrolysis of ATP is used to drive exergonic reactions.

B. The phosphate groups of ATP are held together by unstable bonds that can be broken to release energy.

If chlorophyll a is blocked from absorbing light, what would be the effect on the ability of the plant to do photosynthesis? A. The plant will have an enhanced ability to carry out light-independent reactions B. The plant will have a decreased ability to carry out light-dependent reactions C. The plant will have an enhanced ability to carry out light-dependent reactions D. The plant's ability to carry out photosynthesis will be unchanged, as one of the accessory pigments can fill in for chlorophyll a

B. The plant will have a decreased ability to carry out light-dependent reactions

A tomato plant is mutated with gamma radiation. A cellular analysis reveals that ATP synthase complexes found in the thylakoid membrane are inserted backwards into the membrane. What is the most likely outcome of this error? A. The ATP synthase will pump protons into the stroma in this orientation B. The proton gradient in the thylakoid space will not be able to be used to generate ATP C. A proton gradient will not be established in the thylakoid space in response to the activation of photosystem II D. The thylakoid membrane will become permeable to protons as a result of this change E. This change is not likely to have any effect on the function of the ATP synthase enzyme with respect to its role in photosynthesis

B. The proton gradient in the thylakoid space will not be able to be used to generate ATP

A particular chemical reaction is exergonic. What can you say about the relationship between the reactants and the products in this exergonic reaction? A. The reactants cannot spontaneously react to generate the products. B. The reactants have more free energy than the products. C. The reactants are likely more disordered and the products are likely more ordered. D. The reactants likely have lower enthalpy than the products.

B. The reactants have more free energy than the products.

If the antenna complex did not exist in a particular plant mesophyll cell, what effect would that have on photosynthesis? A. There would be no expected effect on photosynthesis B. These cells would have a reduced capacity to generate glucose C. These cells would be unable to absorb any light energy D. These cells would be able to fix more carbon dioxide

B. These cells would have a reduced capacity to generate glucose

Why are the components of the electron transport chain embedded in the inner mitochondrial membrane rather than floating freely in the cytoplasm of mitochondrial matrix? A. To separate the ATP from the ADP. B. To generate and maintain the proton gradient essential for ATP production. C. Because NADH cannot localize to the mitochondrial matrix. D. Because electrons cannot float in the matrix.

B. To generate and maintain the proton gradient essential for ATP production.

It is summer, and you are excited about going to your local amusement park, and specifically about riding the new roller coaster that was just built. You imagine waiting at the top of the stairs for the roller coaster to pull into the station, climbing into the car, strapping yourself into the seatbelt, and pulling down the harness. You can imagine the cars slowly chugging up to the top of the first hill, coming down on the other side, and the excitement you expect to feel as you go along for the ride. Of all of the things that you have imagined, which is an example of potential energy? A. Climbing into the car B. Waiting at the top of the stairs for the roller coaster to pull into the station C. The roller coaster car going up the first hill D. Pulling down the harness

B. Waiting at the top of the stairs for the roller coaster to pull into the station

The Krebs cycle occurs in the mitochondria. There are nine biochemical reactions involved in the Krebs cycle, and they are highly ordered. Select the correct order from the following choices. (Note: These are abbreviated and do not show NAD, ADP, ATP, or FAD.) A. acetyl-CoA joins the Kreb cycle and unites with oxaloacetate forming citrate which forms beta-ketoglutarate which forms succinyl-CoA which forms succinate which forms fumarate which forms malate which forms oxaloacetate B. acetyl-CoA joins the Kreb cycle and unites with oxaloacetate forming citrate which forms alpha-ketoglutarate which forms succinyl-CoA which forms succinate which forms fumarate which forms malate which forms oxaloacetate C. acetyl-CoA joins the Kreb cycle and unites with oxaloacetate forming citrate which forms alpha-ketoglutarate which forms succinyl-CoA which forms succinate which forms malate which forms fumarate which forms oxaloacetate D. acetyl-CoA joins the Kreb cycle and unites with oxaloacetate which forms alpha-ketoglutarate forming citrate which forms succinyl-CoA which forms succinate which forms fumarate which forms malate which forms oxaloacetate

B. acetyl-CoA joins the Kreb cycle and unites with oxaloacetate forming citrate which forms alpha-ketoglutarate which forms succinyl-CoA which forms succinate which forms fumarate which forms malate which forms oxaloacetate OCASSFMO

The energy needed to destabilize existing chemical bonds and start a chemical reaction is called A. kinetic energy. B. activation energy. C. potential energy. D. free energy.

B. activation energy.

Proteins are polymers formed of structural units called: A. fatty acids. B. amino acids. C. nucleotides. D. phosphate groups. E. monosaccharides.

B. amino acids.

Chlorophyll b absorbs green wavelengths of light that chlorophyll a cannot absorb. In this respect, chlorophyll b acts as A. a light absorber in the green light. B. an accessory pigment. C. a more efficient pigment. D. an energizer for photosynthetic bacteria.

B. an accessory pigment.

Enzymes function to: A. react with other enzymes to form a product. B. catalyze chemical reactions. C. transport molecules and ions across membranes. D. regulate messages between cells.

B. catalyze chemical reactions.

High temperatures can cause proteins in a cell to denature. This can be reversed by heat shock proteins that function as _______. A. catalysts B. chaperones C. proteasome D. ribosomes E. polymerases

B. chaperones

In eukaryotes, photosynthesis takes place inside ________. A. the Golgi apparatus B. chloroplasts C. the cytoplasm D. central vacuoles E. mitochondria

B. chloroplasts

Oxidation and reduction reactions are chemical processes that result in a gain or loss of A. protons. B. electrons. C. atoms. D. molecules. E. neutrons.

B. electrons.

The synthesis of sugar molecules through the process of photosynthesis requires energy absorbed from sunlight. Bearing this in mind, what kind of reaction is photosynthesis? A. exergonic B. endergonic C. catabolic D. feedback

B. endergonic

Organic molecules have a carbon backbone and _____ such as -OH and -NH2 that can form hydrogen bonds. A. R groups B. functional groups C. extension groups D. chemical groups

B. functional groups

A calorie is the commonly used unit of chemical energy. It is also the unit of A. light. B. heat. C. magnetism. D. sound. E. radioactivity.

B. heat.

Proteins digested by trypsin in the stomach are broken down to amino acids in A. anabolic reactions. B. hydrolysis reactions. C. denaturation reactions. D. dehydration reactions.

B. hydrolysis reactions

In a chemical reaction, 1,3-bisphosphoglycerate + ADP yields 3-phosphoglycerate plus ATP. The delta G for this reaction is A. greater than zero. B. less than zero. C. equal to zero. D. cannot be determined.

B. less than zero.

The biological macromolecule that is least soluble in water is a(n): A. carbohydrate. B. lipid. C. enzyme D. protein. E. nucleic acid.

B. lipid.

These biological compounds are non-polar and insoluble in water: A. carbohydrates B. lipids C. proteins D. nucleic acids

B. lipids

The information storage molecules of cells are called: A. enzymes. B. nucleic acids. C. proteins. D. hormones. E. phospholipids.

B. nucleic acids.

In his 1771 experiments, Joseph Priestly determined that plants added something to the air that allow an animal to survive. What do we now know that plants contribute to the air that is essential for animals (and other organisms)? A. organic sugars B. oxygen C. carbon dioxide D. water

B. oxygen

Proteins are created with: A. phosphodiester bonds. B. peptide bonds. C. triglycerides. D. polysaccharides.

B. peptide bonds.

Biological membranes contain bilayers containing mostly ______. A. oils B. phospholipids C. prostaglandins D. triglycerides E. cholesterol

B. phospholipids

The digestive enzyme pepsin works in the acidic environment of the stomach to hydrolyze peptide bonds in ______. A. carbohydrate B. protein C. DNA D. lipid

B. protein

In plants, production of NADPH A. occurs during the Calvin cycle. B. requires electrons originally found in water. C. occurs in the absence of light. D. requires the production of a proton gradient.

B. requires electrons originally found in water.

RNA molecules that also act as enzymes are given the name A. coenzymes. B. ribozymes. C. allosteric enzymes. D. cofactors.

B. ribozymes.

In 1932, researchers Emerson and Arnold showed that the rate of photosynthesis saturated at a lower light intensity than expected for the number of individual chlorophyll molecules. From this observation they determined A. that high light intensities destroyed most pigment molecules B. that pigments were clustered in photosystems and they were measuring saturation of pigments in reaction centers C. that plants must be able to fix carbon before their pigments can absorb light D. that they had overestimated the number of chlorophyll molecules present in their test organism

B. that pigments were clustered in photosystems and they were measuring saturation of pigments in reaction centers

---A nucleic acid contains uracil, allowing you to conclude that: A. this nucleic acid is DNA. B. this nucleic acid is RNA. C. this nucleic acid could be either DNA or RNA.

B. this nucleic acid is RNA.

Three fatty acids bonded together with a glycerol are found in a(n): A. chlorophyll pigment. B. triglyceride. C. enzyme. D. alcohol. E. phospholipid.

B. triglyceride.

Common lipids for energy storage are: A. steroids. B. triglycerides. C. cholesterols. D. waxes. E. phospholipids.

B. triglycerides.

Illuminated chloroplasts deprived of carbon dioxide A. will make glucose, but will not produce ATP or NADH. B. will accumulate ATP, NADPH, and not produce glucose. C. will not make ATP, NADH, or glucose. D. will not make ATP, but will make NADH and glucose.

B. will accumulate ATP, NADPH, and not produce glucose.

Which reaction illustrates a hydrolysis reaction? A)) A > B + C+ H2O B)) A + B + H2O > C C)) A + H2O > B + C D)) A + B > C + H2O

C)) A + H2O > B + C

The chloroplast is a membrane-bound organelle that is surrounded by an outer membrane. Aside from the outer membrane of the chloroplast, how many other types of membranes can be found inside the chloroplast? A. 0 B. 1 C. 2 D. 3 E. 4

C. 2

If you take into account the amount of ATP generated by ATP synthase per molecule of NADH and per molecule of FADH2 produced, and the number of ATP molecules produced by substrate-level phosphorylation, what is the predicted energy yield of the Krebs cycle, per molecule of glucose in eukaryotic cells? A. 10 ATP B. 30 ATP C. 20 ATP D. 1 ATP E. 2 ATP

C. 20 ATP

A DNA strand contains 20 purines and 26 pyrimidines. How many purines will the complementary strand contain? A. 13 B. 20 C. 26 D. 40 E. 52

C. 26

A low fat cookie with 2 grams of fat, 10 grams of carbohydrate, and 2 grams of protein contains: A. 14kcal B. 56kcal C. 66kcal D. 126kcal

C. 66kcal

The number of glyceraldehyde-3-phosphate molecules that would be produced from 24 turns of the Calvin cycle would be A. 4 B. 6 C. 8 D. 12 E. 48

C. 8

A particular reaction has a positive delta G. However, this reaction takes many years to proceed in the absence of enzyme. Why is this the case? A. This reaction does not proceed spontaneously. B. The initial free energy of the reactants is much less than the final free energy of the products. C. A certain amount of activation energy is required for the reaction to proceed. D. This reaction does not obey the second law of thermodynamics.

C. A certain amount of activation energy is required for the reaction to proceed.

What molecule can oxidize NADH? A. Ubiquinone B. Glucose C. Acetaldehyde D. Isocitrate E. Lactate

C. Acetaldehyde

Metabolic reactions fall under two general categories: anabolic and catabolic. What type of chemical reactions are these two classes of metabolic reactions? A. Both anabolic and catabolic reactions are exergonic. B. Anabolic reactions are exergonic reactions, whereas catabolic reactions are endergonic. C. Anabolic reactions are endergonic reactions, whereas catabolic reactions are exergonic. D. Both anabolic and catabolic reactions are endergonic.

C. Anabolic reactions are endergonic reactions, whereas catabolic reactions are exergonic.

Which plants utilize a specialized carbon fixation enzyme and a unique cell type/organization to reduce the problems of photorespiration? A. CAM B. C3 C. C4 D. Arctic E. Desert

C. C4

The formula for glucose is C6H12O6. What is the formula for a polymer made by linking ten glucose molecules together by dehydration synthesis? A. C60H120O60 B. C60H111O51 C. C60H102O51 D. C60H100O50

C. C60H102O51

The cyclic carbon fixation reactions are also known as the A. Krebs cycle. B. tri carboxylic acid cycle. C. Calvin cycle. D. citric acid cycle. E. glycolysis.

C. Calvin cycle.

Where do the carbon atoms in glucose come from? A. NADPH B. Oxygen C. Carbon dioxide D. Water E. Sunlight

C. Carbon dioxide

You arrive late to a biological seminar. However, just as you enter the room, you hear the speaker referring to the "five-prime end" and the "three-prime end" of a macromolecule. Immediately, you know that they are talking about a: A. carbohydrate. B. protein. C. DNA. D. lipid.

C. DNA.

A new antibiotic has been developed. It acts as a noncompetitive inhibitor. How will this antibiotic affect delta G for the enzyme-catalyzed reaction? A. Delta G will increase B. Delta G will decrease C. Delta G will be unaffected

C. Delta G will be unaffected

Which experimental modifications would most effectively help to determine the sequence of reactions and the reaction intermediates in the Calvin cycle? A. Exposing the cells to alternating periods of light and darkness B. Exposing the cells to radiolabeled O2 instead of 14CO2 C. Exposing the cells to 14CO2 for various time intervals D. Varying the amount of water the cells are exposed to

C. Exposing the cells to 14CO2 for various time intervals

Sudan IV, a dye that binds to nonpolar molecules, is used to detect the presence of macromolecules in food. Sudan IV would test positive in the presence of what macromolecule? A. Starch B. DNA C. Fats D. Chitin E. Hemoglobin

C. Fats

Hexokinase is an enzyme that binds specifically to glucose and converts it into glucose 6-phosphate. The activity of hexokinase is suppressed by glucose 6-phosphate, which binds to hexokinase at a location that is distinct from the active site. This is an example of what? A. Cofactor binding B. Allosteric activation C. Feedback inhibition D. Competitive inhibition

C. Feedback inhibition

During what step of glycolysis are two ATP molecules required? A. Cleavage and rearrangement B. Acetyl-CoA formation C. Glucose priming D. Oxidation E. Pyruvate formation

C. Glucose priming

A bobcat is feeding on a white-tailed deer. It first eats the liver, which is rich in stored sugars. In what form would sugar be stored in the deer's liver? A. Glucose B. Maltose C. Glycogen D. Amylose E. Cellulose

C. Glycogen

When oxygen is unavailable during heavy exercise what process do muscle cells use for energy generation? A. Glycolysis coupled with alcohol fermentation. B. Aerobic respiration. C. Glycolysis coupled with lactate fermentation. D. Anaerobic respiration.

C. Glycolysis coupled with lactate fermentation.

When oxygen is unavailable during heavy exercise what process do muscle cells use for energy generation? A. Anaerobic respiration. B. Aerobic respiration. C. Glycolysis coupled with lactate fermentation. D. Glycolysis coupled with alcohol fermentation.

C. Glycolysis coupled with lactate fermentation.

Which amino acid is least soluble in water? A. Alanine B. Glutamine C. Isoleucine D. Glycine

C. Isoleucine

Humans are unable to get metabolic energy from cellulose because: A. cellulose contains very little chemical energy. B. cellulose is not part of a normal diet. C. cellulose digesting enzymes are absent from the human gut. D. cellulose does not taste good. E. cellulose is present in large quantities in the gut.

C. cellulose digesting enzymes are absent from the human gut.

Which statement about the P/O ratio is true? A. It shows that cellular respiration is an inefficient process. B. It depends on the number of electron acceptor sites on ATP synthase. C. It represents the amount of ATP produced by oxidative phosphorylation. D. It has been understood for centuries based on theoretical calculations. E. It represents the amount of ATP made per glucose molecule.

C. It represents the amount of ATP produced by oxidative phosphorylation.

Yogurt contains galactose and glucose, which are generated when bacterial enzymes act on milk sugars. What is the main source of the galactose in yogurt? A. Maltose B. Sucrose C. Lactose D. Fructose E. Glycogen

C. Lactose

Carbon dioxide and water can combine to form glucose, water and oxygen. What is required for that process to occur? A. Nothing, this is a spontaneous reaction B. Energy from the process of cellular respiration C. Light energy from the sun D. Mitochondria

C. Light energy from the sun

The nucleotide-containing molecule commonly used to carry electrons in the cell is A. ADP. B. ATP. C. NAD+. D. pyruvic acid.

C. NAD+

What oxidizing agent is used to temporarily store high energy electrons harvested from glucose molecules in a series of gradual steps in the cytoplasm? A. FADH2 B. ADP C. NAD+ D. Oxygen

C. NAD+

Enzyme 1 converts substrate A into product B. Is this an example of a metabolic pathway? A. Yes. This is a metabolic pathway that includes feedback inhibition. B. Yes. This is a simple metabolic pathway. C. No. This only describes one chemical reaction. A metabolic pathway includes multiple chemical reactions. D. No. A metabolic pathway must include an inhibitory step.

C. No. This only describes one chemical reaction. A metabolic pathway includes multiple chemical reactions.

In green plants, which photosystem absorbs photons to excite electrons in the reaction center? A. Photosystems I, II and III B. Photosystem I C. Photosystems I and II D. Photosystem III E. Photosystem II

C. Photosystems I and II

If a plant's stomata were always closed, how would this affect the plant's ability to make glucose? A. Plants would be able to make more sugar than normal. B. There would be no effect on the ability of the plant to make glucose. C. Plants would make less sugar than normal.

C. Plants would make less sugar than normal.

In the light-independent reactions of photosynthesis, CO2 is added to a five-carbon molecule known as A. ribose. B. deoxyribose. C. RuBP. D. CAM. E. cellulose.

C. RuBP.

The Law of Thermodynamics that states that increases in entropy are favored is the A. Fourth Law of Thermodynamics. B. Third Law of Thermodynamics. C. Second Law of Thermodynamics. D. First Law of Thermodynamics.

C. Second Law of Thermodynamics.

As electrons move along the electron transport chain, they lose potential energy. How is the energy that is released used by the cell? A. The energy is converted directly into ATP B. The energy is used to pump NAD+ into the cytoplasm so it can be used in glycolysis C. The energy is used to transport protons against their concentration gradient D. The energy is used to pump electrons along the electron transport chain

C. The energy is used to transport protons against their concentration gradient

In order to reuse an enzyme after the conclusion of an enzyme catalyzed reaction, what must occur? A. The enzyme has to be resynthesized. B. The enzyme has to decrease entropy. C. The enzyme has to separate itself from the product. D. Changes into an active form.

C. The enzyme has to separate itself from the product.

Egg whites consist primarily of water and the protein albumin. When you fry an egg, why does the egg white turn from clear to white? A. The protein becomes dissociated. B. The protein acquires tertiary structure. C. The protein becomes denatured. D. The protein becomes dehydrated.

C. The protein becomes denatured.

The ultimate source of energy for humans comes from what source? A. Plants B. Animals C. The sun D. Air E. Water

C. The sun

Vitamin D can be synthesized by the body from a derivative of cholesterol. Given this information, predict vitamin D's solubility. A. Vitamin D is soluble in both water and fat. B. Vitamin D is water-soluble. C. Vitamin D is fat-soluble. D. Vitamin D is not soluble in either water or fat.

C. Vitamin D is fat-soluble.

The covalent bonds connecting monomer units in sugars can be formed by the removal of a water molecule. This reaction is referred to as: A. a hydrolysis reaction. B. an oxidation-reduction reaction. C. a dehydration reaction. D. a condensation reaction.

C. a dehydration reaction.

Phospholipids are made up of: A. a glycerol and three fatty acids. B. four fused carbon rings. C. a phosphate, two fatty acids and a glycerol. D. five-carbon rings with two nonpolar tails.

C. a phosphate, two fatty acids and a glycerol.

When the substrate is bound to the enzyme, the shape of the enzyme may change slightly, leading to A. a great range of possible catalytic activities. B. more possible products of the reaction. C. an induced fit. D. a greater supply of activation energy. E. more permanent binding through intimate total contact.

C. an induced fit.

The term oxidation is derived from the name of the element oxygen. This is reasonable, because oxygen A. passes electrons to many other types of molecules. B. contains more electrons than are needed. C. attracts electrons very strongly. D. can be oxidized by accepting electrons.

C. attracts electrons very strongly.

Fall leaf color on deciduous trees is a result of A. the reduction in the production of accessory pigments. B. the production of more accessory pigments because of the cooler temperatures. C. cessation of chlorophyll production, which allows the accessory pigments to be revealed. D. the increased angle of the sun during the fall, which reflects more of the accessory pigments.

C. cessation of chlorophyll production, which allows the accessory pigments to be revealed.

The inorganic non-protein components that participate in enzyme catalysis are known as A. products. B. coenzymes. C. cofactors. D. substrates. E. reactants.

C. cofactors.

A molecule that closely resembles the shape of a substrate for an enzyme would most likely serve as a: A. noncompetitive inhibitor B. allosteric inhibitor C. competitive inhibitor D. allosteric activator

C. competitive inhibitor

Lipids are the only class of macromolecules that contain: A. amino acids. B. nucleotides. C. fatty acids. D. phosphate groups. E. monosaccharides.

C. fatty acids.

Your friend is having difficulty keeping track of the energy flow from glucose through glycolysis, the Krebs cycle and electron transport. Your best advice would be to: A. follow the protons. B. follow ATP production. C. follow the electrons. D. follow NAD+ production.

C. follow the electrons.

What type of monomer does ATP represent? A. glycerol B. amino acid C. nucleotide D. fatty acid E. monosaccharide

C. nucleotide

Denaturation disrupts the secondary and tertiary structure of proteins. However, denaturation is not strong enough to disrupt what interaction that is relevant to protein structure? A. ionic bonds B. van der Waals attraction C. peptide bonds D. hydrophobic exclusion E. hydrogen bonds

C. peptide bonds

You arrive late to a biological seminar. However, just as you enter the room, you hear the speaker referring to the "amino end" and the "carboxyl end" of a macromolecule. Immediately, you know that they are talking about a: A. carbohydrate. B. DNA. C. protein. D. lipid.

C. protein.

When an atom or molecule gains one or more electrons, it is said to be A. oxidized. B. polarized. C. reduced. D. energized.

C. reduced.

If the Calvin cycle were to be temporarily restricted, the highest concentration of NADPH would likely be in the A. thylakoid space. B. chloroplast outer membrane. C. stroma. D. thylakoid membrane.

C. stroma.

Energy is defined as A. movement. B. heat. C. the capacity to do work. D. change.

C. the capacity to do work.

The plant hormone abscisic acid (ABA) is involved in the regulation of photorespiration. Based on this information, ABA likely plays a role in A. the photoelectric effect. B. cyclic photophosphorylation. C. the opening and closing of stomata. D. absorption of light by accessory pigments. E. noncyclic photophosphorylation.

C. the opening and closing of stomata.

NADPH is made by A. chemiosmosis. B. the Calvin cycle. C. the passing of electrons from photosystem I to an electron transport chain. D. glycolysis. E. the Krebs cycle.

C. the passing of electrons from photosystem I to an electron transport chain.

What is the color of light that chlorophylls absorb that has the highest energy? A. green B. yellow-orange C. violet-blue D. red

C. violet-blue

- glucose is present in potatoes and - glucose is present in wood. Both are glucose molecules but one can be used by humans to synthesize ATP and one cannot. Based on this information, what is the best explanation on why humans can only digest one of the glucose types? A. - glucose is a chain and - glucose is a ring. B. Only - glucose can form polysaccharides. C. - glucose is C6H12O6 and - glucose is C5H12O6. D. - glucose and - glucose are stereoisomers with OH groups oriented differently.

D. - glucose and - glucose are stereoisomers with OH groups oriented differently.

How many water molecules are produced during the formation of a triglyceride from fatty acids and glycerol? A. 0 B. 1 C. 2 D. 3 E. 4

D. 3

In the light-independent reactions, when CO2 is added to a molecule of Ribulose 1,5-bisphosphate (RuBP) the immediate product is A. citric acid. B. glucose. C. glyceraldehyde-3-phosphate. D. 3-phosphoglycerate. E. pyruvate.

D. 3-phosphoglycerate.

In order to generate one glucose molecule, the Calvin cycle has to turn how many times? A. 1 B. 2 C. 3 D. 6 E. 12

D. 6

Cardiac muscle cells need to generate significant amounts of ATP to allow for constant contractile activity. As a result, they primarily depend upon beta-oxidation of fatty acids, which has a higher energy yield than the catabolism of glucose. What would be the ATP yield for beta-oxidation of a hypothetical 10-carbon fatty acid? A. 50 ATP B. 35 ATP C. 32 ATP D. 62 ATP E. 65 ATP

D. 62 ATP

What products of light reactions of photosynthesis are used in the Calvin cycle? A. ADP and NADP B. Carbon dioxide and water C. Glucose and oxygen D. ATP and NADPH E. Oxygen and protons

D. ATP and NADPH

How and where is ATP made in a eukaryotic cell? A. ATP is only made in the mitochondria in response to chemiosmosis. B. ATP is made in all compartments of the cell in response to endergonic reactions and is used to drive exergonic reactions in the cell. C. ATP can be made by an enzyme complex that uses the energy of protons moving down their concentration gradient from the mitochondrial matrix to the cytoplasm to make the ATP. D. ATP can be made by direct phosphorylation of ADP in the cytoplasm, and by an enzyme complex that uses the energy from a proton gradient to drive ATP synthesis in the mitochondria. It can also be made in other locations in the cell, depending on the cell type.

D. ATP can be made by direct phosphorylation of ADP in the cytoplasm, and by an enzyme complex that uses the energy from a proton gradient to drive ATP synthesis in the mitochondria. It can also be made in other locations in the cell, depending on the cell type.

An organism acquires a mutation in the gene for pyruvate dehydrogenase that renders the protein unable to bind NADH. What is the most likely consequence of this mutation? A. Fats will be oxidized at a higher rate than normal. B. Pyruvate will not be able to enter the mitochondria. C. Pyruvate oxidation will cease to occur. D. ATP synthesis will proceed at a high rate even when the cell has an ample supply. E. Substrate level phosphorylation will cease to occur.

D. ATP synthesis will proceed at a high rate even when the cell has an ample supply.

Phosphofructokinase (PFK) is an enzyme that converts fructose 6-phosphate to fructose 1,6-bisphosphate, by adding a phosphate group. This is the first committed step of the metabolic pathway of glycolysis, and thus it is very tightly regulated. AMP binds to PFK at a site distinct from the binding site for fructose 6-phosphate, and stimulates the formation of fructose 1,6-bisphosphate. ATP binds to PFK at a site distinct from the binding site for fructose 6-phosphate, and inhibits the formation of fructose 1,6-bisphosphate. There are other regulators of this enzyme as well. What is the role of AMP in this example?A. Competitive inhibitor B. Noncompetitive inhibitor C. Allosteric inhibitor D. Allosteric activator E. Catalyst

D. Allosteric activator

Plants that show a pattern of stomatal opening and closing that is the reverse of C3 plants are called A. Calvin cycle. B. temperate. C. C4. D. CAM.

D. CAM.

Seth purchased five pounds of live crayfish and realized that the outer shells were made of a tough carbohydrate similar to that used to make the carapace of a cockroach. What do you think the outer shells of the crawfish are made of? A. Amylopectin B. Cellulose C. Glycogen D. Chitin E. Fibrin

D. Chitin

One way to generate acetyl-CoA is to convert pyruvate into acetyl-CoA by stripping off a C02 molecule. The removal of CO2 is referred to as what type of reaction? A. Acetylation B. Glycolytic C. Carboxylation D. Decarboxylation

D. Decarboxylation

L-lysine is an essential amino acid and must be supplied in the diet. By comparison, the stereoisomer D-lysine is not biologically active. Why can your body only utilize one form? A. Since the L form and D form are enantiomers, they will bind together and inhibit utilization of the D form. B. Since the L form and D form are chiral molecules, they will bind together and inhibit utilization of the D form. C. Antibodies recognize the D form and destroy it before your body can use it for nutritional purposes. D. Enzymes can only recognize a single, specific stereoisomer.

D. Enzymes can only recognize a single, specific stereoisomer.

While conducting an experiment, you realize that a competitive inhibitor was interfering with your reaction. How could you overcome this problem? A. Add an allosteric activator to the reaction. B. Add a non-competitive inhibitor to the reaction. C. Add a cofactor to the reaction. D. Increase the concentration of the correct substrate in the reaction.

D. Increase the concentration of the correct substrate in the reaction.

In the reaction catalyzed by aconitase, the conversion of citrate to isocitrate is inhibited by fluoroacetate. Fluoroacetate is used as a pesticide. Why is this an effective pesticide? A. It inhibits the electron transport chain. B. It inhibits ATP synthase. C. It inhibits glycolysis. D. It inhibits the Krebs cycle. E. It inhibits pyruvate oxidation.

D. It inhibits the Krebs cycle.

People who are lactose intolerant can often consume some products made from milk such as cheese and yogurt. By comparison, people with a true milk allergy, which involves an immune response to milk protein, cannot consume milk or products made from milk. Given this information, what can you conclude about milk? A. The protein that causes a true milk allergy is lactose. B. All people who are lactose intolerant are also allergic to milk. C. Yogurt contains live and active cultures of Lactobacillus acidophilus bacteria and therefore prevents an allergic response in people with a true milk allergy. D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies.

D. Lactose is a carbohydrate, not a protein and is therefore not the cause of true milk allergies.

The myoglobin protein, which carries oxygen in muscle cells, has only the first three levels of protein structure. What can you infer about myoglobin? A. Myoglobin is not helical or pleated B. Myoglobin lacks hydrogen bonds C. Myoglobin is made of nucleic acids D. Myoglobin is made of only one polypeptide chain

D. Myoglobin is made of only one polypeptide chain

What is the oxidized form of the most common electron carrier that is needed for both glycolysis and the Krebs cycle? A. FAD B. pyruvate C. ATP D. NAD+ E. acetyl-CoA

D. NAD+

In a phospholipid, the phosphate would be found in which part of a membrane? A. In the bilayer, interacting with water. B. On the surface of the membrane, shielded from water. C. In the bilayer, shielded from water. D. On the surface of the membrane, interacting with water.

D. On the surface of the membrane, interacting with water.

Kinases are enzymes that can phosphorylate (transfer phosphate groups onto) macromolecules such as proteins. A particular kinase, Kinase 1 is known to promote cell division. It promotes cell division by phosphorylating Protein X. Phosphorylation of Protein X activates Protein X. Once activated, Protein X stimulates the production of other proteins such as Protein Y and Z that directly promote cell division. In order to function, Kinase 1 requires the presence of Metal A. However, in the presence of Protein A, Kinase 1 is nonfunctional. From the description, what is considered the substrate of Kinase 1? A. Protein Y B. Protein Z C. Metal A D. Protein X E. Protein A

D. Protein X

Luke sprained his ankle, tearing some of the collagen protein that forms his ligaments. Some types of collagen consist of three polypeptide chains twisted together to form a rope-like strand. What level of protein structure does this rope-like strand represent? A. Primary B. Secondary C. Tertiary D. Quaternary

D. Quaternary

Inside the chloroplast, where are organic molecules made? A. On the thylakoid membrane B. Inside the thylakoid C. Between the outer and inner membranes D. Stroma E. On the cristae

D. Stroma

A biochemist wants to control the initial substrate-level phosphorylation that occurs in the tracheal cells of grasshoppers once glucose has crossed the plasma membrane. He has access to the following inhibitors: Rotenone - an electron transport chain inhibitor, Oligomycin - an ATP synthase inhibitor, and TLN-232, an inhibitor of glycolysis. Which inhibitor should he use to slow down initial substrate-level phosphorylation that occurs once glucose has crossed the plasma membrane? A. Oligomycin B. None of these inhibitors would be effective in preventing substrate-level phosphorylation C. Rotenone D. TLN-232

D. TLN-232

Aerobic respiration is ultimately the reaction of glucose with oxygen to generate carbon dioxide, water, and energy. However, in a cell this process involves the transfer of electrons from glucose to carriers such as NAD+ over a lengthy series of steps. Why don't cells employ the direct reaction of glucose with oxygen to generate energy? A. The direct reaction of oxygen with glucose would be much less efficient. B. The direct reaction of oxygen with glucose does not spontaneously occur. C. Oxygen and glucose are localized in different subcellular compartments. D. The direct transfer of electrons from glucose to oxygen occurs via a combustion reaction that is incompatible with life.

D. The direct transfer of electrons from glucose to oxygen occurs via a combustion reaction that is incompatible with life.

Cytochromes contain a heme group similar to that in hemoglobin. The iron atom (Fe) in the center of the group can be oxidized and reduced. If someone was suffering from iron deficiency anemia, what stage of cellular respiration would be most affected? A. Fermentation B. Glycolysis C. The Krebs cycle D. The electron transport chain

D. The electron transport chain

All of the reactions of cellular respiration that occur after glycolysis take place in what part of the eukaryotic cell? A. The plasma membrane B. The chloroplast C. The cytoplasm D. The mitochondria E. The nucleus

D. The mitochondria

Based on the graph below, what are the optimal temperatures for the human enzyme and the hotsprings prokaryote enzyme? A. The optimal temperature for the human enzyme is 46oC; the optimal temperature for the hotsprings prokaryote enzyme is 79oC. B. The optimal temperature for the human enzyme is 30oC; the optimal temperature for the hotsprings prokaryote enzyme is 60oC. C. The optimal temperature for the human enzyme is 35oC; the optimal temperature for the hotsprings prokaryote enzyme is 65oC. D. The optimal temperature for the human enzyme is 40oC; the optimal temperature for the hotsprings prokaryote enzyme is 72oC.

D. The optimal temperature for the human enzyme is 40oC; the optimal temperature for the hotsprings prokaryote enzyme is 72oC.

A current problem in modern medicine is the development of drug resistance mutations. This occurs when a mutation arises in a patient making him/her resistant to a drug and thus rendering the drug useless in treating a specific disease. Many useful drugs are competitive inhibitors of specific enzymes, and the drug-resistance mutations prevent the binding of the drug. These types of mutations, in addition to preventing competitive inhibitor binding, can also sometimes reduce the activity of the enzyme. Why is that the case? A. These mutations most likely affect an allosteric site on the enzyme B. These mutations lower the activation energy of the reaction catalyzed by the enzyme C. Binding to the competitive inhibitor is essential for the function of the enzyme D. These mutations most likely change the shape of the active site of the enzyme

D. These mutations most likely change the shape of the active site of the enzyme

Why do we have storage macromolecules, such as fats, in our bodies? A. Macromolecules, such as fats, are a convenient way to store kinetic energy. B. Human cells can directly capture the energy of sunlight through photosynthesis and store it as macromolecules such as fats. C. Breaking down macromolecules, such as fats, is an endergonic process. D. We can break down these macromolecules to provide energy for the endergonic reactions in our bodies.

D. We can break down these macromolecules to provide energy for the endergonic reactions in our bodies.

In the absence of oxygen, can cells utilize the electron transport chain? A. Yes, all cells can make use of the electron transport chain in the absence of oxygen via fermentation. B. No, oxygen is the primary electron acceptor in electron transport chains in all cell types. C. No, oxygen is a required cofactor for the complexes in the electron transport chain. D. Yes, in the case that a cell can use a terminal electron acceptor other than oxygen, it can make use of the electron transport chain.

D. Yes, in the case that a cell can use a terminal electron acceptor other than oxygen, it can make use of the electron transport chain.

Does ADP contain the capacity to provide energy for the cell? A. No. ADP does not contain any bonds that can be broken to provide energy for the cell. B. Yes. Cleaving the bond between the ribose sugar and the two phosphate groups can provide energy for the cell. C. Yes. ADP has the same capacity to provide energy for the cell as ATP. D. Yes. Cleaving the bond between the terminal phosphate and the phosphate attached to the ribose sugar can provide energy for the cell.

D. Yes. Cleaving the bond between the terminal phosphate and the phosphate attached to the ribose sugar can provide energy for the cell.

Organisms that can manufacture their own chemical energy are called ____________. A. heterotrophs B. oligotrophs C. chemotrophs D. autotrophs

D. autotrophs

At night, the Calvin cycle in a C3 plant A. cannot run, as it requires light energy directly. B. uses a different source of carbon. C. runs in a different place in the plant. D. can still run as long as there is ATP, CO2, and NADPH present.

D. can still run as long as there is ATP, CO2, and NADPH present.

The role of the antenna complex in a photosystem is to A. generate glucose. B. transfer excited electrons to the primary electron acceptor. C. generate NADPH. D. capture photons from sunlight.

D. capture photons from sunlight.

At the pH of most bodily fluids, which functional group will lose a proton and which functional group will accept a proton? A. sulfhydryl; carbonyl B. phosphate; amino C. amino; carboxyl D. carboxyl; amino E. carbonyl; phosphate

D. carboxyl; amino

The simplest and the most common monosaccharide is a six-carbon sugar called: A. galactose. B. lactose. C. cellulose. D. glucose. E. sucrose.

D. glucose

In photosynthesis, carbon fixation occurs: A. in the electron transport chain B. in photosystem I C. in photosystem II D. in the Calvin cycle E. during photorespiration

D. in the Calvin cycle

The photosynthetic electron transport causes the accumulation of protons in which part of the chloroplast? A. matrix B. outer membrane C. stroma D. internal thylakoid space

D. internal thylakoid space

Which type of RNA is used as a template for translation of proteins? A. ribosomal RNA B. micro RNA C. transfer RNA D. messenger RNA

D. messenger RNA

The chemistry of living systems representing all chemical reactions is called A. enzymology. B. catabolism. C. thermodynamics. D. metabolism. E. anabolism.

D. metabolism.

Since rubisco can either fix carbon or oxidize RuBP, what condition will be most favorable for glucose production? A. high temperatures B. dry climate C. high oxygen environment D. moderate temperatures

D. moderate temperatures

Carbohydrates are composed of: A. amino acids. B. fatty acids and glycerol. C. nucleotides. D. monosaccharides.

D. monosaccharides.

One of the disadvantages of the C4 pathway is that it requires _____ than C3 photosynthesis. A. more O2 B. more NADPH C. more light D. more ATP E. a much higher temperature

D. more ATP

You recently identified a novel protein that contains several membrane-spanning domains. You predict that the amino acids embedded in the membrane would have ______ side groups. A. negatively charged B. positively charged C. polar uncharged D. nonpolar

D. nonpolar

DNA and RNA contain functional units known as: A. peptides. B. enzymes. C. amino acids. D. nucleotides. E. fatty acids.

D. nucleotides.

The Calvin cycle requires all of the following except A. carbon dioxide. B. NADPH. C. ATP. D. oxygen. E. water.

D. oxygen.

Amino acids are linked together by peptide bonds in a ____ A. polysaccharide. B. nucleic acid. C. phospholipid. D. polypeptide. E. starch.

D. polypeptide.

In an enzyme-catalyzed reaction, the reactant is called the A. product. B. coenzyme. C. catalyst. D. substrate.

D. substrate.

You return home to find that your baby brother has scattered his toy trains and trucks all over the floor of your room. As you begin to pick up the toys and put them away, you realize that even though he is just a baby, he has clearly mastered ' A. the first law of thermodynamics. B. free energy. C. potential energy. D. the second law of thermodynamics.

D. the second law of thermodynamics.

Fructose and galactose both have six carbon atoms, twelve hydrogen atoms and six oxygen atoms, just like glucose. A friend of yours says: "Since those sugars have the same number of atoms, they should have the same name." You answer: "While they do have the same number and type of atoms, A. they are named differently because one is found in RNA and the other in DNA." B. they are named differently because they cannot be converted into glucose." C. they are named differently because they have different secondary structure." D. they are named differently because they are isomers of the monosaccharide, glucose." E. they are all polysaccharides and have slightly different functions within organisms and therefore have different names."

D. they are named differently because they are isomers of the monosaccharide, glucose."

You are working on a research project that involves a mutational analysis of the light harvesting complex Lhca1, which is an important light harvesting complex found in plants. Your labmate asks where this complex is located. You say it is in the A. plasma membrane. B. outer chloroplast membrane. C. the stroma. D. thylakoid membrane. E. inner chloroplast membrane.

D. thylakoid membrane.

Flattened sacs of internal membranes associated with photosynthesis are called A. cristae. B. the stroma. C. photosystems. D. thylakoids. E. chloroplasts.

D. thylakoids

DNA is made up of: RNA is made up of:

DNA: adenine, thymine, guanine, cytosine RNA: adenine, uracil, guanine, cytosine RNA= Uracil DNA= Thymine

How many molecules of CO2 are needed to generate one molecule of glucose? A. 2 B. 3 C. 4 D. 5 E. 6

E. 6

A candy bar contains 108 calories per serving. There are 4 grams of carbohydrate, 5 grams of protein, and 8 grams of fat in a serving. How many of the calories come from fat? A. 16 B. 20 C. 36 D. 45 E. 72

E. 72

To replace fossil fuels, the world must find a way of producing fuel from renewable energy. One of the most promising fuels of the future is hydrogen, which could potentially be produced in algae using the power of sunlight. Green algae contain enzymes (hydrogenases) that can convert hydrogen ions (H+) and electrons to hydrogen gas (H2). The hydrogen ions used by the hydrogenase come from A. water. B. ATP synthase. C. organic sugars. D. rubisco. E. ATP.

E. ATP.

To form NADH from NAD+, two electrons and a proton are removed from an organic molecule. What term best describes the reaction in which electrons and a proton are removed from an organic molecule? A. Condensation B. Decarboxylation C. Isomerization D. Reduction E. Dehydrogenation

E. Dehydrogenation

The energy released in the mitochondrial electron transport chain is used to transport protons where? A. Into the cytoplasm B. Into the nucleus C. Into the mitochondrial matrix D. Into the endoplasmic reticulum E. Into the intermembrane space of the mitochondria

E. Into the intermembrane space of the mitochondria

Kinases are enzymes that can phosphorylate (transfer phosphate groups onto) macromolecules such as proteins. A particular kinase, Kinase 1 is known to promote cell division. It promotes cell division by phosphorylating Protein X. Phosphorylation of Protein X activates Protein X. Once activated, Protein X stimulates the production of other proteins such as Protein Y and Z that directly promote cell division. In order to function, Kinase 1 requires the presence of Metal A. However, in the presence of Protein A, Kinase 1 is nonfunctional. From the description, what is considered a cofactor of Kinase 1? A. Protein A B. Protein X C. Protein Z D. Protein Y E. Metal A

E. Metal A

Regardless of the electron or hydrogen acceptor used, one of the products of fermentation is always: A. pyruvate B. alcohol C. ADP D. ATP E. NAD+

E. NAD+

Light-dependent reactions generate A. light. B. ATP and CO2. C. ATP and NADPH. D. glucose and O2. E. O2, ATP, and NADPH.

E. O2, ATP, and NADPH.

The aquatic plant Elodea is commonly used to study photosynthesis. You put some Elodea in a test tube, shine light on the plant, and count the bubbles that were released under varying conditions. Which results would you expect to see in your analysis of photosynthetic rate? A. the number of bubbles increase indefinitely with increased illumination B. as light intensity increases, the number of bubbles increase and then rapidly decrease C. at high light intensities, the number of bubbles increase when the temperature is increased to human body temperature (37 degrees C) D. at low light intensities, the number of bubbles increase as temperature increases and the number of bubbles decrease as carbon dioxide concentration decreases E. at high light intensities, the number of bubbles increase as carbon dioxide concentration increases

E. at high light intensities, the number of bubbles increase as carbon dioxide concentration increases

In an experiment described in a chemistry lab book, the directions state that after mixing two chemicals (A and B) and waiting 5 minutes that A will be oxidized. This means that A. chemical A has gained energy in the form of heat from chemical B. B. chemical A has gained electrons from chemical B. C. chemical A has reacted with oxygen. D. chemical A has lost energy in the form of heat to chemical B. E. chemical A has lost electrons to chemical B.

E. chemical A has lost electrons to chemical B.

Both photosystems I and II A. involve the generation of oxygen. B. are found in the stroma. C. lose an electron to a primary electron acceptor that passes the electron down an electron transport chain leading to the generation of ATP. D. involve the splitting of water to donate an electron to the reaction center. E. contain a reaction center composed of chlorophyll a.

E. contain a reaction center composed of chlorophyll a.

Carbohydrates are polymers formed of structural units called: A. amino acids. B. fatty acids. C. nucleotides. D. glycerols. E. monosaccharides.

E. monosaccharides.

Light consists of units of energy called A. pigments. B. calories. C. neutrons. D. electrons. E. photons.

E. photons.

Clusters of chlorophyll and accessory pigments are called ________. A. chloroplasts B. the Golgi apparatus C. cristae D. photosynthetic membranes E. photosystems

E. photosystems

Molecules that absorb light are called A. electron carriers. B. absorbers. C. photosynthesizers. D. enzymes. E. pigments.

E. pigments.

Dicyclohexylcarbodiimide (DCCD) is a chemical that disrupts the function of ATP synthase. Why will treatment with DCCD cause a cell to die? A. the pH of the intermembrane space becomes too high (alkaline) B. the cell cannot form a proton gradient across the inner mitochondrial membrane C. glucose cannot be oxidized to form pyruvate D. electrons cannot travel down the electron transport chain E. protons cannot flow from the intermembrane space into the matrix

E. protons cannot flow from the intermembrane space into the matrix

A photosystem channels the excitation energy gathered by absorption of light by any one of the pigment molecules to a specific reaction center chlorophyll, which in turn passes the energy to A. cytochrome. ' B. accessory pigments. C. photosystem II. D. the secondary electron center. E. the primary electron acceptor.

E. the primary electron acceptor.

Most atmospheric oxygen comes from photosynthesis. From which molecules is the oxygen derived? A. chlorophyll b B. glucose C. carbon dioxide D. chlorophyll a E. water

E. water

For photosynthesis in green plants, the electron donor for the light dependent reaction is A. RuBP. B. oxygen. C. chlorophyll II. D. carbon dioxide. E. water.

E. water.

DNA and RNA difference

RNA= Uracil, DNA= Thymine


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