Question 1

Which of the following statements about prokaryotic cell morphology is correct?

Accepted Answer

Cell morphology does not predict physiology, ecology, or pathogenicity.

Question 2

A spherical bacterium that divides along three perpendicular planes and forms clusters is best described as:

Accepted Answer

Staphylococcus

Question 3

Which of the following best explains why a higher surface-to-volume ratio ($$\frac{S}{V}) $$benefits prokaryotic cells?

Accepted Answer

It allows for faster nutrient and waste exchange, supporting rapid growth and evolution.

Question 4

A bacterium is found to have a single, closed, circular chromosome and several plasmids. What is the most likely advantage conferred by the plasmids?

Accepted Answer

They provide resistance to antibiotics or metabolic advantages.

Question 5

Which of the following is a function of inclusion bodies in prokaryotic cells?

Accepted Answer

Energy storage and reduction of osmotic pressure

Question 6

Gas vesicles in aquatic bacteria such as cyanobacteria serve what primary function?

Accepted Answer

Buoyancy regulation to optimize position in the water column

Question 7

Which of the following statements about the prokaryotic cytoplasmic membrane is true?

Accepted Answer

In archaea, the membrane can be a monolayer with ether-linked isoprene units.

Question 8

Which of the following best describes the function of ABC transporters in prokaryotes?

Accepted Answer

They use ATP hydrolysis to actively transport specific solutes across the membrane.

Question 9

What is the main structural difference between Gram-positive and Gram-negative bacterial cell walls?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer, while Gram-negative bacteria have a thin peptidoglycan layer and an outer membrane.

Question 10

Which component of the Gram-negative outer membrane is responsible for its toxicity in animals?

Accepted Answer

Lipid A of lipopolysaccharide (LPS)

Question 11

A researcher isolates a prokaryote with a cell wall containing pseudomurein and $$\beta(1,3)$$ glycosidic bonds. This organism is most likely:

Accepted Answer

An archaeon

Question 12

Which of the following is NOT a function of the prokaryotic cell wall?

Accepted Answer

Serves as the main site of ATP synthesis

Question 13

Which of the following best describes the role of teichoic acids in Gram-positive bacteria?

Accepted Answer

They bind cations such as Ca$$^{2+}$$ and Mg$$^{2+}$$ for import into the cell.

Question 14

A bacterium is found to be highly resistant to bile salts and lipophilic antibiotics. Which structural feature most likely contributes to this resistance?

Accepted Answer

Outer membrane with lipopolysaccharide (LPS)

Question 15

Which of the following is a function of the capsule found on some bacterial cells?

Accepted Answer

Prevents immune system recognition and aids in attachment to surfaces

Question 16

Which of the following best explains why Gram-negative bacteria are generally harder to kill with antibiotics than Gram-positive bacteria?

Accepted Answer

Their outer membrane acts as a barrier to many toxic substances.

Question 17

Which of the following structures is responsible for motility in many prokaryotes and is powered by the proton motive force?

Accepted Answer

Flagella

Question 18

A scientist observes a prokaryotic cell with numerous short, hair-like structures that allow it to attach to surfaces. These structures are most likely:

Accepted Answer

Fimbriae

Question 19

Which of the following best describes the arrangement of membrane proteins in the prokaryotic cytoplasmic membrane?

Accepted Answer

Polarity of proteins matches their location in the membrane, with both integral and peripheral proteins present.

Prokaryotic Cell Structure and Function – Comprehensive Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard