Question 1

Which of the following statements correctly describes a key difference between the two prokaryotic domains, Bacteria and Archaea?

Accepted Answer

Archaea have ether-linked membrane lipids, while Bacteria have ester-linked lipids.

Question 2

Which of the following is NOT an extracellular structure commonly found in prokaryotes?

Accepted Answer

Nucleoid

Question 3

What is the average diameter of a typical prokaryotic cell?

Accepted Answer

$$0.5-5\ \mu m$$

Question 4

Which feature of Gram-negative bacteria makes them generally more resistant to antibiotics than Gram-positive bacteria?

Accepted Answer

Presence of an outer membrane containing lipopolysaccharide

Question 5

A scientist stains two bacterial samples: one turns purple, the other turns pink. What does this indicate about their cell wall structure?

Accepted Answer

Purple indicates Gram-positive; pink indicates Gram-negative.

Question 6

Which of the following best describes passive transport in prokaryotic cells?

Accepted Answer

Movement of substances down their concentration gradient without energy input.

Question 7

A bacterial cell is placed in a hypertonic solution. What is the most likely outcome?

Accepted Answer

The cell will lose water and shrink (plasmolysis).

Question 8

Which structure is primarily responsible for bacterial motility?

Accepted Answer

Flagella

Question 9

How do periplasmic flagella benefit spirochetes in terms of movement and survival?

Accepted Answer

They enable corkscrew motion, allowing movement through viscous environments.

Question 10

Which statement best describes the organization of DNA in prokaryotic cells?

Accepted Answer

DNA is organized in a nucleoid region without a surrounding membrane.

Question 11

During bacterial cell division, how is DNA replication coordinated with cell growth?

Accepted Answer

DNA replication and cell division are tightly coupled, often overlapping.

Question 12

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

Accepted Answer

Storage of genetic material

Question 13

What is the primary function of bacterial endospores?

Accepted Answer

Allow bacteria to survive extreme conditions such as heat and desiccation

Question 14

Which of the following bacteria is known for causing disease in humans via endospore formation?

Accepted Answer

Bacillus anthracis

Question 15

Why are antibiotics that target peptidoglycan synthesis generally ineffective against human cells?

Accepted Answer

Human cells lack peptidoglycan in their cell walls.

Question 16

Which antibiotic mechanism specifically targets bacterial ribosomes, inhibiting protein synthesis?

Accepted Answer

Tetracycline binding to the 30S ribosomal subunit

Question 17

A patient is infected with Clostridium difficile, a spore-forming bacterium. Which property of endospores makes this infection particularly difficult to eradicate?

Accepted Answer

Endospores can survive extreme environmental conditions, including heat and chemicals.

Question 18

Which of the following best explains why Gram-positive bacteria are more susceptible to lysozyme than Gram-negative bacteria?

Accepted Answer

Gram-positive bacteria have a thick, exposed peptidoglycan layer.

Question 19

Which of the following equations correctly represents the calculation of cell surface area for a spherical prokaryotic cell?

Accepted Answer

$$A = 4\pi r^2$

Question 20

A Gram-negative bacterium is exposed to penicillin. Which structural feature reduces the effectiveness of penicillin against this bacterium?

Accepted Answer

Presence of an outer membrane that limits drug access to peptidoglycan

Prokaryotic Cell Structure and Function: Study Notes for Microbiology

Guida di studio - Domande di pratica

Study guide - Flashcard