$$ \text{ATP} \rightarrow \text{ADP} + \text{P}_i $$

Question 1

Which of the following best describes the primary function of Type IV fimbriae in bacteria?

Accepted Answer

Attachment to solid surfaces and twitching motility on moist surfaces

Question 2

A bacterium is observed to move toward a source of glucose. This behavior is best described as:

Accepted Answer

Chemotaxis

Question 3

Which energy source is directly responsible for the rotation of bacterial flagella?

Accepted Answer

Proton motive force across the cell membrane

Question 4

A scientist is studying a Gram-negative bacterium that exports toxins using an ABC transporter. Which secretion system is most likely involved?

Accepted Answer

Type I secretion system

Question 5

Which of the following is a unique feature of the Type IV secretion system in Agrobacterium tumefaciens?

Accepted Answer

It can secrete both protein and DNA

Question 6

The Sec-dependent pathway in bacteria is responsible for which of the following?

Accepted Answer

Translocating proteins across the plasma membrane using ATP hydrolysis

Question 7

Which of the following best explains why Gram-negative bacteria face additional challenges in protein secretion compared to Gram-positive bacteria?

Accepted Answer

They have an additional outer membrane that proteins must cross

Question 8

A bacterium with peritrichous flagella would be expected to have:

Accepted Answer

Flagella distributed over the entire cell surface

Question 9

Which secretion system is used by Yersinia pestis to inject virulence factors directly into host cells?

Accepted Answer

Type III secretion system

Question 10

A mutation in the SecA protein would most likely affect which cellular process?

Accepted Answer

Translocation of proteins across the plasma membrane

Question 11

Which of the following best describes the role of chemoreceptors in bacterial chemotaxis?

Accepted Answer

Detecting chemical gradients to direct movement

Question 12

A patient is infected with Neisseria meningitidis. Which structure is most important for the bacterium’s attachment to host tissues?

Accepted Answer

Type IV fimbriae

Question 13

Which of the following equations best represents the energy requirement for the Sec-dependent pathway?

Accepted Answer

$$ 	ext{ATP} ightarrow 	ext{ADP} + 	ext{P}_i $$

Question 14

Which of the following is NOT a function of bacterial fimbriae?

Accepted Answer

Protein synthesis

Question 15

A researcher observes a bacterium that moves away from high concentrations of oxygen. This is an example of:

Accepted Answer

Aerotaxis

Question 16

Which of the following best explains why all protein secretion pathways require energy?

Accepted Answer

Transporting proteins across membranes is energetically unfavorable

Question 17

Which secretion system is most likely to be involved in the export of antimicrobial drugs by a Gram-negative bacterium?

Accepted Answer

Type I secretion system

Question 18

Which of the following is a real-world consequence of Agrobacterium tumefaciens Type IV secretion system?

Accepted Answer

Formation of crown gall disease in plants

Question 19

Which of the following best describes the distribution of flagella in a lophotrichous bacterium?

Accepted Answer

A tuft of flagella at one or both ends

Question 20

A mutation that disrupts the proton gradient across the bacterial cell membrane would most directly affect which process?

Accepted Answer

Flagellar rotation and motility

Prokaryotic Structure & Function: Adhesion, Motility, and Secretion

Study Guide - Practice Questions