lecture quiz 2 Flashcards
There are many similarities between the process of photosynthesis and the process of cellular respiration. Which of the following is a not accurate comparison of photosynthesis and cellular respiration?
- The Calvin cycle and the citric acid cycle have largely opposite functions.
- Both photosynthesis and cellular respiration involve redox reactions.
- Only cellular respiration involves an electron transport chain that creates a proton motive force driving ATP synthesis.
- The intermembrane space of mitochondria serves a similar function as the thylakoid space of chloroplasts.
Only cellular respiration involves an electron transport chain that creates a proton motive force driving ATP synthesis.
If all reactions of pyruvate oxidation and the citric acid cycle that use NAD+/NADH as electron carriers instead used FAD+/FADH2 as electron carriers, how many more/fewer ATP molecules would be produced per molecule of glucose through aerobic cellular respiration?
8 fewer ATP would be produced.
The human hormone insulin causes liver cells to increase the rate they convert glucose to glycogen for storage. Based on this information, what might occur in a liver cell exposure to insulin?
The amount of the enzyme converting glucose to glycogen might increase.
If someone ingested a toxin that prevents pyruvate from entering the mitochondria, what would happen to citrate and phosphofructokinase.
The amount of citrate in the cell would decrease, leading to an increase in the activity of phosphofructokinse.
The hydrolysis of the disaccharide sucrose results in the formation of the monosaccharides glucose and fructose, and the ∆G of this reaction is -29.3 kJ/mol. Sucrase is an enzyme that is able to catalyze the hydrolysis of sucrose. What would happen if you added the enzyme sucrase to a solution of sucrose?
- The activation energy of the reaction would decrease.
- The ∆G would of the reaction would not change.
- The rate of sucrose hydrolysis would increase.
Which of the following statements about the role of ATP in cell signalling is correct?
- ATP has no involvement in signal transduction pathways.
- ATP is involved in the activation of G protein-coupled receptors.
- ATP is involved in the formation of a secondary messenger.
- All of the other options are correct.
ATP is involved in the formation of a secondary messenger.
Which of the following statements about exergonic chemical reaction is true?
- There is a release of energy because the energy needed to form new bonds in the products, is less than the energy released from breaking of bonds in the reactants.
- There is a release of energy because the energy needed to break bonds in the reactants, is less than the energy released when forming new bonds in the products.
- There is a release of energy due to the breakage of high-energy bonds in the reactants.
- There is a release of energy due to the breakage of high-energy bonds in the products.
There is a release of energy because the energy needed to break bonds in the reactants, is less than the energy released when forming new bonds in the products.
What could result in the continuous activation of a cell signalling pathway?
mutation
A mutation resulting in the inactivation of a protein phosphatase.
Imagine you are working in a lab and studying three species of yeast, which are eukaryotic organisms. The first species (Species A) of yeast generates ATP using aerobic cellular respiration. The second species of yeast (Species B) generates ATP using alcohol fermentation. The third species of yeast (Species C) generates ATP using lactic acid fermentation. Which of the following statements are true?
- Only Species A can grow without oxygen.
- Species B needs to use 15-16 molecules of glucose to generate the same amount of ATP that is made by Species A using one molecule of glucose.
- Species C produces more carbon dioxide than does Species B.
- All of the other answers are true.
Species B needs to use 15-16 molecules of glucose to generate the same amount of ATP that is made by Species A using one molecule of glucose.
ATP is an important molecule in cellular energetics. Which of the following statements is false?
- ATP hydrolysis can provide the energy required for mechanical work in a cell.
- ATP is made during cellular respiration by substrate-level phosphorylation, as well as through chemiosmosis which involves the enzyme ATP synthase.
- ATP hydrolysis is an endergonic reaction.
- None of the other answers are false.
ATP hydrolysis is an endergonic reaction.
Many antibiotics, which are molecules that are toxic to bacteria, function as enzyme inhibitors. Imagine that both Antibiotic A and Antibiotic B inhibit the ribosome. Antibiotic A kills the bacteria. In contrast, Antibiotic B only temporarily stops growth, with the bacteria remaining alive and able to resume growth when the antibiotic is removed. Which of the following statements provides a reasonable explanation for the difference between Antibiotic A and Antibiotic B?
- Antibiotic A is a non-reversible enzyme inhibitor whereas Antibiotic B is a reversible enzyme inhibitor.
- Antibiotic A is a competitive enzyme inhibitor whereas Antibiotic B is a non-competitive enzyme inhibitor.
- Antibiotic A is a reversible enzyme inhibitor whereas Antibiotic B is a non-reversible enzyme inhibitor.
- Antibiotic A is a non-competitive enzyme inhibitor whereas Antibiotic B is a competitive enzyme inhibitor.
Antibiotic A is a non-reversible enzyme inhibitor whereas Antibiotic B is a reversible enzyme inhibitor.
What is true about the two metabolic processes aerobic cellular respiration and fermentation
Both include reactions that involve electron carriers.
Which of the following statements about quorum sensing are true? Choose the best answer only.
- There is no specificity in quorum sensing meaning all bacteria can respond to all quorum sensing molecules.
- Quorum sensing is most similar to paracrine signalling in multicellular organisms.
- Quorum sensing is not involved in coordinating group behaviour in bacteria.
- All of the other options are true.
Quorum sensing is most similar to paracrine signalling in multicellular organisms.
Imagine you are working in a lab, and you are performing two chemical reactions. You notice that Reaction A occurs much faster than Reaction B, and that both reactions release the same amount of heat. Which of the following conclusions can be made from your observation?
- Reaction A has the same activation energy as Reaction B, and the ∆G of Reaction A is more negative (i.e., a larger negative number) than the ∆G for Reaction B.
- Reaction A has a higher activation energy than Reaction B, and the ∆G of Reaction A is the same as the ∆G of Reaction B.
- Reaction A has the same activation energy as Reaction B, and the ∆G of Reaction A is less negative (i.e., a smaller negative number) than the ∆G for Reaction B.
- Reaction A has a lower activation energy than Reaction B, and the ∆G of Reaction A is the same as the ∆G of Reaction B.
Reaction A has a lower activation energy than Reaction B, and the ∆G of Reaction A is the same as the ∆G of Reaction B.
