Question 1

Which of the following is a primary function of polyhydroxybutyric acid (PHB) inclusions in prokaryotic cells?

Accepted Answer

They store excess carbon as a polymer for later use.

Question 2

A bacterium is found to contain numerous granules of elemental sulfur. What is the most likely metabolic strategy of this organism?

Accepted Answer

Chemoautotrophy using reduced sulfur compounds as electron donors.

Question 3

Which inclusion allows aquatic phototrophic bacteria to regulate their position in the water column?

Accepted Answer

Gas vesicles

Question 4

Magnetotactic bacteria use magnetosomes to orient themselves in magnetic fields. What is the main component of these magnetosomes?

Accepted Answer

Iron-containing minerals

Question 5

Which of the following storage polymers is a polymer of glucose?

Accepted Answer

Glycogen

Question 6

A researcher observes that a bacterium can float to the surface of a pond. Which structure is most likely responsible for this ability?

Accepted Answer

Gas vesicles

Question 7

Which of the following best describes the chemical composition of gas vesicles in aquatic bacteria?

Accepted Answer

They are composed of crystalline protein.

Question 8

If a bacterium stores phosphate in the form of polyphosphate granules, which equation best represents the polymerization of phosphate?

Accepted Answer

$n \mathrm{PO}_4^{3-} \rightarrow (\mathrm{PO}_4^{3-})_n$

Question 9

Which of the following inclusions is most likely to be found in bacteria living in environments with fluctuating carbon availability?

Accepted Answer

Polyhydroxyalkanoate (PHA) granules

Question 10

A bacterium is isolated from a sulfur-rich hot spring. Which inclusion would you expect to find in high abundance within its cytoplasm?

Accepted Answer

Elemental sulfur granules

Question 11

Which of the following is NOT a function of storage inclusions in prokaryotic cells?

Accepted Answer

Providing buoyancy in aquatic environments

Question 12

Which equation best represents the formation of glycogen from glucose monomers in bacteria?

Accepted Answer

$n \mathrm{C}_6\mathrm{H}_{12}\mathrm{O}_6 \rightarrow (\mathrm{C}_6\mathrm{H}_{10}\mathrm{O}_5)_n + n \mathrm{H}_2\mathrm{O}$

Question 13

Which of the following statements about PHB and PHA is correct?

Accepted Answer

Both are lipid-like polymers used for carbon storage.

Question 14

A scientist wants to distinguish between gas vesicles and magnetosomes in aquatic bacteria. Which method would be most effective?

Accepted Answer

Electron microscopy to visualize crystalline protein vs. iron minerals

Question 15

Which of the following inclusions is most directly involved in the formation of bacterial blooms in lakes?

Accepted Answer

Gas vesicles

Question 16

Which of the following is a correct description of the role of magnetosomes in bacteria?

Accepted Answer

They allow bacteria to orient and move along magnetic field lines.

Question 17

Which inclusion would you expect to be most abundant in a bacterium growing in a phosphate-rich environment?

Accepted Answer

Polyphosphate granules

Question 18

Which of the following best explains why bacteria form storage inclusions during periods of nutrient excess?

Accepted Answer

To store nutrients for use during periods of scarcity.

Question 19

A bacterium is found to have both gas vesicles and magnetosomes. What advantage does this combination provide in an aquatic environment?

Accepted Answer

It enables the bacterium to control its position vertically and orient itself along magnetic fields.

Exam 2 (Lecture 7) Non-Universal Prokaryotic Structures: Storage Inclusions and Intracellular Structures

Study Guide - Practice Questions