BIO110 Final Exam Clicker Questions

You are studying a diploblastic organism without a body cavity (coelom). This organism probably belongs to the phylum A. Porifera. B. Platyhelminthes. C. Nematoda. D. Cnidaria.

D. Cnidaria.

What cellular conditions favor increased activity of the electron transport chain and oxidative phosphorylation? Low oxygen concentrations Low NADH concentrations High NAD+ High ADP concentrations

High ADP concentrations

Monotropa uniflora - Ghost Plant, Indian Pipe derives sugars from fungi that are intimately associated with trees. What is the relationship between this plant and the trees? Mutualism Parasitism Commensalism

Parasitism

Which one of the following molecules is necessary for glycolysis to proceed normally? Oxygen. Water. Carbon Dioxide. NAD+.

NAD+

To sustain high rates of glycolysis under anaerobic conditions, cells require functioning mitochondria. oxygen. oxidative phosphorylation of ATP. NAD+. All of the above are correct.

NAD+.

Does an organism with no chloroplasts fix CO2? (all white) Yes No

No

Which of these molecules in cell respiration is the most electronegative? Carbon dioxide Glucose Oxygen Water

Oxygen

MCAT Question: In the redox reaction: pyruvate + NADH + H+ ⇋ lactate + NAD+ which reactant is oxidized and which is reduced? NADH is reduced and pyruvate is oxidized Lactate is reduced and NAD+ is oxidized Pyruvate is reduced and NADH is oxidized Lactate is reduced and pyruvate is oxidized

Pyruvate is reduced and NADH is oxidized

How are electrons transferred from the Krebs cycle for use in the electron transport chain? Reduction of NAD+ Oxidation of ATP Reduction of ATP Oxidation of NAD+

Reduction of NAD+

At the end of glycolysis, how many total molecules of ATP have been synthesized from ADP from a single molecule of glucose? 4 36 2 38

4

During alcohol metabolism in humans, alcohol dehydrogenase converts ethanol to acetylaldehyde and a molecule of NADH is produced. Next, acetylaldehyde oxidase converts acetylaldehyde to acetate and another molecule of NADH is produced. Finally, acetyl-CoA synthase produces acetyl CoA and the Acetyl CoA then enters the Krebs cycle. Assuming that the Krebs cycle and the electron transport chain are working efficiently, how many TOTAL molecules of NADH are produced in the catabolism of one molecule of ethanol? 3 4 5 6

5

The voltage between the inner mitochondrialmembrane and matrix is variable. Which of the following conditions would lead to a decrease in voltage? An increase in NADH A decrease in ATP synthesis An increase in oxygen A decrease in oxygen

A decrease in oxygen

If the electron transport chain between Photosystem II and Photosystem I begins to work inefficiently then ATP production will decrease. no NADPH will be oxidized. water production will decrease. oxygen production will increase.

ATP production will decrease.

Drugs known as uncouplers facilitate diffusion of protons across the mitochondrial membrane. When such a drug is added, what will happen to ATP synthesis and oxygen consumption, if the rates of glycolysis and the Krebs cycle stay the same? Both ATP synthesis and oxygen consumption will decrease. ATP synthesis will decrease; oxygen consumption will increase. ATP synthesis will increase; oxygen consumption will decrease. Both ATP synthesis and oxygen consumption will increase. ATP synthesis will decrease; oxygen consumption will stay the same.

ATP synthesis will decrease; oxygen consumption will stay the same.

Which of the following is not an advantage of the cuticle in arthropods? Physical protection. Structural support for muscles. Prevents desiccation. Allows for greater gas exchange.

Allows for greater gas exchange.

Which of these is not a chordate characteristic? A notochord. A dorsal nerve cord. A post anal tail. An exoskeleton.

An exoskeleton.

Why does muscle contraction result in higher body temperature? Because ATP phosphorylation has a +ΔG Because ATP hydrolysis has a -ΔG Because ATP hydrolysis has a +ΔG Because ATP phosphorylation has a -ΔG

Because ATP hydrolysis has a -ΔG

In which organisms does glycolysis occur? Neither aerobic nor anaerobic organisms Both aerobic and anaerobic organisms Aerobic organisms only Anaerobic organisms only

Both aerobic and anaerobic organisms

MCAT Question: Which of the following best describes the respective free energy changes for the one-step combustion of glucose in the presence of oxygen as compared to the multi-step oxidation of glucose during cellular respiration, assuming both reactions occur under identical conditions? Both reactions have the same change in free energy The combustion has a higher change in free energy More information is needed to answer the question The combustion has a lower change in free energy

Both reactions have the same change in free energy

A bifurcation in the tree of animal evolutionary history separates the Radiata from the Bilateria. Which of the following also describes this bifurcation? Diploblasts vs. triploblasts. Coelomates vs. pseudocoelomates. Protostomes vs. deuterostomes. True tissues vs. no true tissues.

Diploblasts vs. triploblasts.

Aerobic cellular respiration involves the flow of electrons from one chemical species to another: which of the following best describes this process? Electrons are transferred from glucose to carbon dioxide Electrons are transferred from oxygen to water Electrons are transferred from glucose to oxygen Electrons are transferred from oxygen to glucose

Electrons are transferred from glucose to oxygen

Photuris lucicrescens is a bioluminescent coleopteran. In other words, the lightning bug is a beetle that can glow in the dark. Is bioluminescence an endergonic or exergonic reaction and what is the ΔG of bioluminescence? Endergonic reaction with positive ΔG. Exergonic reaction with positive ΔG. Endergonic reaction with negative ΔG. Exergonic reaction with negative ΔG.

Endergonic reaction with positive ΔG.

A mutation occurs in the chloroplasts of a lettuce plant, causing its thylakoid membranes to become more permeable to charged ions. How might this mutation affect the Calvin cycle? Fewer carbohydrates would be produced by the Calvin cycle. More carbohydrates would be produced by the Calvin cycle. There would be no change to the Calvin cycle.

Fewer carbohydrates would be produced by the Calvin cycle.

What is true of a down hill reaction? It is spontaneous, exergonic, and has a -ΔG It is spontaneous, exergonic, and has a +ΔG It is nonspontaneous, exergonic, and has a -ΔG It is spontaneous, endergonic, and has a +ΔG

It is spontaneous, exergonic, and has a -ΔG

You have a friend who lost 15 pounds of fat on a diet. Where did the fat go? It was released as CO2 and H2O. It was converted to heat and then released. It was converted to ATP, which weighs less than fat. It was broken down into fatty acids and glycerol, then eliminated from the body. It was converted to adipose and went down the drain.

It was released as CO2 and H2O.

Which of the following characteristic(s) can be used to distinguish a parazoan (sponge) from a eumetazoan? Presence of flagellated cells. Lack of true tissues. Ingestive heterotropy. All of the above characteristics can be used to distinguish a parazoan from a eumetazoan.

Lack of true tissues.

You are working with a mutant plant that you think has chloroplasts that lack photosystem II (PSII), even though it is able to live. How could you determine if PSII is missing from the plant's chloroplasts? Test for the fixation of CO2 in the dark Test for the presence of sugar Test for the presence of oxygen in light Test for thylakoid presence in the chloroplasts

Test for the presence of oxygen in light

MCAT Question: ATP hydrolysis is a spontaneous chemical reaction under standard physiological conditions: what is always true of spontaneous reactions? That the products of the reaction have higher free energy than the reactants That the reaction occurs slowly That the products of the reaction have lower free energy than the reactants That the reaction occurs quickly

That the products of the reaction have lower free energy than the reactants

If you applied a herbicide that affected the ability of NADPH to be oxidized, which aspect of photosynthesis would be most immediately affected? ATP synthesis. The Calvin Cycle. Photolysis. The electron transport chain between Photosystem I and Photosystem II.

The Calvin Cycle.

The Calvin cycle is considered light-independent because it can occur in darkness. However, most often the Calvin cycle takes place in sunlight. Which of the following explains why? The enzymes involved in the Calvin cycle are unable to bind substrates in the dark. Sunlight is important in activating carbon fixation in the Calvin cycle. The Calvin cycle requires ATP and NADPH, which require sunlight to be produced. RuBP regeneration requires sunlight in order to occur and continue the Calvin cycle.

The Calvin cycle requires ATP and NADPH, which require sunlight to be produced.

What powers the ATP synthase rotary motor? Pyruvate The H+ gradient ATP hydrolysis Glucose

The H+ gradient

MCAT Question: ATP hydrolysis involves the hydrolysis of what bond? The bond linking the 1st phosphate to the 2nd phosphate The bond linking the 2nd phosphate to the 3rd phosphate The bond linking 1st phosphate to adenine Either of the bonds on the terminal phosphate

The bond linking the 2nd phosphate to the 3rd phosphate

A flask of duckweed (an aquatic plant) in water is placed under a bank of lights on a 12-hour light, 12-hour dark cycle, next to a control flask containing only water. Assuming no change in water temperature, which flask will have the lowest dissolved oxygen (DO) concentration, and at what time? DO will be the same between the control and the duckweed-containing flask. DO will always be higher in the flask with duckweed compared to the control. DO will always be lower in the flask with duckweed compared to the control. The flask with duckweed will have the lowest DO at the end of the dark cycle and the highest DO at the end of the light cycle.

The flask with duckweed will have the lowest DO at the end of the dark cycle and the highest DO at the end of the light cycle.

If a zygote from an animal with indeterminate cleavage splits in half at the eight cell stage, what is the most likely result? The formation of identical twins. The death of the zygote. The formation of fraternal twins. Either A or C could happen.

The formation of identical twins.

MCAT Question: How does the free energy stored by ATP compare to the free energy stored by ADP under standard physiological conditions? The free energy stored by ATP is positive and greater than the free energy stored by ADP, which is also positive The free energy stored by ATP is positive; the free energy stored by ADP is negative The free energy stored by ATP is negative and less than the free energy stored by ADP, which is also negative The free energy stored by ADP is positive and greater than the free energy stored by ATP, which is also positive

The free energy stored by ATP is positive and greater than the free energy stored by ADP, which is also positive

The oxidation of glucose to CO2 and H2O is highly exergonic: G = -636 kcal/mole. Why doesn't glucose spontaneously combust? The glucose molecules lack the activation energy at room temperature. There is too much CO2 in the air. CO2 has higher energy than glucose. The formation of six CO2 molecules from one glucose molecule decreases entropy. The water molecules quench the reaction.

The glucose molecules lack the activation energy at room temperature.

ATP hydrolysis under standard biochemical conditions has ΔG<0 which implies which of the following about the reaction under these conditions? The hydrolysis reaction is exothermic Cleavage of the phosphate bond that occurs during hydrolysis does not require an input of energy The hydrolysis reaction decreases entropy The hydrolysis reaction is spontaneous

The hydrolysis reaction is spontaneous

Photosynthesis can be divided into two steps: the light-dependent reactions and the Calvin cycle. Which of the following is true regarding these two steps? The light-dependent reactions take place in the thylakoid membrane, and the Calvin cycle takes place in the stroma. The Calvin cycle converts water molecules into oxygen gas as a byproduct of its reactions. During the light-dependent reactions, carbon dioxide is fixed to produce sugars that form glucose. The light-dependent reactions use ATP from the Calvin cycle, and the Calvin cycle uses energy from absorbed sunlight.

The light-dependent reactions take place in the thylakoid membrane, and the Calvin cycle takes place in the stroma.

A reaction has a ∆G of -5.6 kcal/mol. Which of the following would most likely be true? The reaction could be coupled to power an endergonic reaction with a ∆G of +8.8 kcal/mol. The reaction would result in a decrease in disorder The reaction could be coupled to power an endergonic reaction with a ∆G of +4.8 kcal/mol. The reaction could be coupled to power an endergonic reaction with a ∆G of -8.8 kcal/mol.

The reaction could be coupled to power an endergonic reaction with a ∆G of +4.8 kcal/mol.

MCAT Question: Kearns-Sayre syndrome is a disease caused by deletions in plasmids that code for proteins of the electron transport chain. What is its inheritance pattern? Autosomal recessive Through the paternal line X-linked Through the maternal line

Through the maternal line

An electron just given up by NADH to the electron transport chain has more energy that one that is pick up by oxygen at the end of the ETC True or False?

True

Evaluate the following statement and determine whether it is True or False: "During cellular respiration in plants, the Krebs cycle takes place within the mitochondria and releases carbon dioxide". False because plants do not have mitochondria. False because the Krebs cycle does not produce carbon dioxide. True because plants have mitochondria and the Krebs cycle releases carbon dioxide. True because all organisms have mitochondria and all organisms produce carbon dioxide.

True because plants have mitochondria and the Krebs cycle releases carbon dioxide.

The presence of a "true" coelom that is completely lined with mesoderm is found in: all members of the radiata. all members of the bilateria. all triploblastic animals all deuterostomes

all deuterostomes

Although radially symmetrical, the Echinoderms are classified with the bilateria because they: are bilaterally symmetrical during early development. have a pseudocoelom. have four tissue layers. have a coelem with mesoderm only on one side.

are bilaterally symmetrical during early development.

The biomass (dry weight) of a tree comes primarily from soil. water. carbon dioxide. organic fertilizer (manure, detritus). sunlight.

carbon dioxide.

Free-living flatworms, roundworms, and segmented worms share all of the following traits except bilateral symmetry. three embryonic tissue layers. presence of a digestive system. digestive tract with mouth and anus. muscle tissue.

digestive tract with mouth and anus.

A molecule that is reduced: gains electrons from another molecule. loses hydrogen ions to another molecule. gains oxygen atoms from another molecule. loses electrons to another molecule.

gains electrons from another molecule.

During cell respiration in aerobic organisms, ____________ serves as the terminal electron acceptor of the Electron Transport chain. carbon dioxide water oxygen NADH

oxygen

Variegated leaves are rarely found in wild plants but are common in garden plants and houseplants because people like their appearance. They are most likely rare in wild plants because variegated plants photosynthesize more than non-variegated plants. photosynthesize less than non-variegated plants. are able to produce more sugars than non-variegated plants. both A and C.

photosynthesize less than non-variegated plants.

By the end of glycolysis most of the energy contained in the starting glucose molecule is now in: NADH pyruvate ATP glucose

pyruvate