Exam 5: Microbial Metabolism

Assume you are working for a chemical company and are responsible for growing a yeast culture that produces ethanol. The yeasts are growing well on the maltose medium but are not producing alcohol. What is the most likely explanation?

Figure 5.1 Which compound is being reduced in the reaction shown in Figure 5.1?

Figure 5.4 How is ATP generated in the reaction shown in Figure 5.4?

The pentose phosphate pathway can be characterized as an anabolic pathway.

Figure 5.7 The graph at the left in Figure 5.7 shows the reaction rate for an enzyme at its optimum temperature. Which graph shows enzyme activity at a higher temperature?

Figure 5.6 The rates of o₂ and glucose consumption by a bacterial culture are shown in Figure 5.6. Assume a bacterial culture was grown in a glucose medium without o₂. Then o₂ was added at the time marked X. The data indicate that

A bacterial culture grown in a glucose-peptide medium causes the pH to increase. The bacteria are most likely

You look in the refrigerator and find some orange drink you had forgotten was there. The drink now has an ʺoffʺ taste and bubbles. What is the most likely explanation for the changes in the drink?

Which of the following compounds is NOT an enzyme?

Figure 5.2 What type of reaction is in Figure 5.2?

Microorganisms that catabolize sugars into ethanol and hydrogen gas would most likely be categorized as

An apoenzyme that loses its coenzyme subunit will be non -functional.

Which of the following statements about substrate-level phosphorylation is FALSE?

Figure 5.8 -Refer to Figure 5.8. In aerobic respiration, where is water formed?

Which of the following statements are TRUE? 1- Electron carriers are located at ribosomes. 2- ATP is a common intermediate between catabolic and anabolic pathways. 3- ATP is used for the long-term storage of energy and so is often found in storage granules. 4-Anaerobic organisms are capable of generating ATP via respiration. 5-ATP can be generated by the flow of protons across protein channels.

Figure 5.8 -In Figure 5.8, the path labeled ʺ2ʺ is the flow of

Fatty acids are oxidized in

In general, ATP is generated in catabolic pathways and expended in anabolic pathways.

Catabolic reactions are generally degradative and hydrolytic.

If a cell is starved for ATP, which of the following pathways would most likely be shut down?