Question 1

Which of the following best describes the primary function of polyhydroxyalkanoate (PHA) inclusions in bacteria?

Accepted Answer

They store carbon in an insoluble form for later energy and carbon needs.

Question 2

A bacterium is found to accumulate large amounts of polyphosphate granules. What is the most likely reason for this accumulation?

Accepted Answer

To store phosphate for nucleic acid and phospholipid synthesis.

Question 3

Which of the following statements about bacterial flagella is CORRECT?

Accepted Answer

Flagella rotate due to the flow of protons through Mot proteins, generating torque.

Question 4

A bacterium with flagella distributed all over its surface is described as having which type of flagellar arrangement?

Accepted Answer

Peritrichous

Question 5

During chemotaxis, how do bacteria like Escherichia coli sense chemical gradients?

Accepted Answer

By measuring changes in chemical concentration over time as they swim.

Question 6

Which of the following best explains the mechanism of group translocation in bacterial cells?

Accepted Answer

The transported substance is chemically modified during transport, using energy from an organic compound.

Question 7

Which equation best represents the energy source for simple transport in bacteria?

Accepted Answer

$$\Delta p = \Delta \Psi - \frac{2.3RT}{F} \Delta pH$$

Question 8

A researcher uses a capillary tube assay to test a new compound. She observes that bacteria accumulate inside the tube. What does this indicate?

Accepted Answer

The compound is an attractant.

Question 9

Which of the following is a unique feature of the ABC transporter system in bacteria?

Accepted Answer

It involves a substrate-binding protein with high affinity for the solute.

Question 10

A bacterium switches its flagellar rotation from counter-clockwise (CCW) to clockwise (CW). What is the immediate effect on its movement?

Accepted Answer

It tumbles, changing direction randomly.

Question 11

Which of the following best describes the role of periplasmic flagella in spirochetes?

Accepted Answer

They provide a corkscrew-like motility and contribute to cell shape.

Question 12

Which of the following transport systems is most likely to be used by a bacterium to import an amino acid against its concentration gradient?

Accepted Answer

ABC transporter system using ATP hydrolysis.

Question 13

Which of the following is a correct statement about the evolutionary relationship between bacterial flagella and ATP synthase?

Accepted Answer

Both are proton-driven molecular motors with structural similarities.

Question 14

A bacterium is exposed to a sudden increase in environmental glucose. Which cellular inclusion is most likely to increase in size as a result?

Accepted Answer

Glycogen granules

Question 15

Which of the following best describes the process of chemotaxis in bacteria?

Accepted Answer

Directed movement in response to chemical gradients, involving changes in flagellar rotation.

Question 16

Which of the following is NOT a function of cellular inclusions in bacteria?

Accepted Answer

Protein synthesis

Question 17

Which of the following best explains why bacteria store nutrients in an insoluble form within inclusions?

Accepted Answer

To prevent osmotic imbalance and allow easy retrieval for metabolism.

Question 18

Which of the following is a key difference between symport and antiport transport systems?

Accepted Answer

Symport moves two substances in the same direction, while antiport moves them in opposite directions.

Question 19

Which of the following best describes the role of Mot proteins in the bacterial flagellum?

Accepted Answer

They act as the stator, allowing protons to flow and generate torque for rotation.

Question 20

A bacterium is found to have a single flagellum at each end of the cell. What is the correct term for this arrangement?

Accepted Answer

Amphitrichous

Cellular Inclusions, Surface Structures, and Chemotaxis in Bacteria

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