Question 1

Which of the following is a key structural difference between prokaryotic and eukaryotic cells?

Accepted Answer

Prokaryotic cells typically have a single circular chromosome and lack a nuclear membrane.

Question 2

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

Accepted Answer

The cell will shrink as water leaves the cytoplasm, a process called plasmolysis.

Question 3

Which component is found in the cell walls of Gram-positive bacteria but not in Gram-negative bacteria?

Accepted Answer

Teichoic acids

Question 4

Which of the following best describes the function of the bacterial glycocalyx?

Accepted Answer

It protects the cell from phagocytosis and aids in adherence to surfaces.

Question 5

Which of the following statements about facilitated diffusion is correct?

Accepted Answer

It uses specific or nonspecific transporter proteins to move substances down their concentration gradient.

Question 6

A Gram-negative bacterium is treated with penicillin. What is the most likely outcome and why?

Accepted Answer

The bacterium will be less susceptible because its thin peptidoglycan layer is protected by an outer membrane.

Question 7

Which of the following is a function of bacterial endospores?

Accepted Answer

Allowing bacteria to survive extreme conditions such as heat and desiccation

Question 8

Which of the following best explains why mycoplasmas are resistant to antibiotics that target cell wall synthesis?

Accepted Answer

They lack a cell wall and instead have sterols in their plasma membrane.

Question 9

Which of the following structures is responsible for the selective permeability of the plasma membrane?

Accepted Answer

Phospholipid bilayer with embedded proteins

Question 10

A scientist observes a bacterium with a single, long, helical spiral shape under the microscope. Which term best describes this morphology?

Accepted Answer

Spirochete

Question 11

Which of the following is a distinguishing feature of eukaryotic cells compared to prokaryotic cells?

Accepted Answer

Presence of membrane-bound organelles such as mitochondria and Golgi apparatus

Question 12

Which of the following best describes the Gram stain mechanism in Gram-positive bacteria?

Accepted Answer

Alcohol dehydrates the thick peptidoglycan, trapping crystal violet-iodine complexes.

Question 13

Which of the following is true regarding the arrangement of bacterial flagella?

Accepted Answer

Flagella can be arranged peritrichously, with many flagella distributed over the entire cell surface.

Question 14

Which of the following best explains why penicillin is considered a 'miracle drug'?

Accepted Answer

It inhibits peptide bridge formation in peptidoglycan, which is not present in human cells.

Question 15

Which of the following is a function of the eukaryotic Golgi apparatus?

Accepted Answer

Modification and sorting of proteins and lipids for secretion or delivery to other organelles

Question 16

A bacterium is observed to survive boiling temperatures and desiccation. Which structure is most likely responsible for this resistance?

Accepted Answer

Endospore

Question 17

Which of the following statements about the endosymbiotic theory is correct?

Accepted Answer

It suggests that mitochondria and chloroplasts were once free-living bacteria engulfed by ancestral eukaryotic cells.

Question 18

Which of the following is a unique feature of archaeal cell walls?

Accepted Answer

They may contain pseudomurein, which lacks N-acetylmuramic acid (NAM) and D-amino acids.

Question 19

Which of the following best describes the movement of water across a semipermeable membrane from an area of low solute concentration to high solute concentration?

Accepted Answer

Osmosis

Question 20

Which of the following is a correct statement about ribosomes in prokaryotic and eukaryotic cells?

Accepted Answer

Prokaryotic cells have 70S ribosomes, while eukaryotic cytoplasm contains 80S ribosomes, but mitochondria and chloroplasts contain 70S ribosomes.

Functional Anatomy of Prokaryotic and Eukaryotic Cells: Microbiology Study Guide

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