Q: Which of the following equations best represents the net movement of water during osmosis across a selectively permeable membrane?

$$\text{Water moves from an area of low solute concentration to an area of high solute concentration}$$

Question 1

Which of the following best describes the main difference between prokaryotic and eukaryotic cells regarding their genetic material?

Accepted Answer

Prokaryotic cells have a single circular chromosome located in the nucleoid, while eukaryotic cells have multiple linear chromosomes contained within a nucleus.

Question 2

A microbiologist observes spherical bacteria arranged in grape-like clusters under the microscope. Which term best describes this arrangement?

Accepted Answer

Staphylococci

Question 3

Which of the following structures is found in prokaryotic cells but not in eukaryotic cells?

Accepted Answer

Peptidoglycan cell wall

Question 4

A patient presents with pharyngitis. A throat swab reveals spherical bacteria arranged in chains. Which organism is most likely responsible?

Accepted Answer

Streptococcus pyogenes

Question 5

Which of the following best explains why penicillin is generally more effective against Gram-positive bacteria than Gram-negative bacteria?

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer that is the primary target of penicillin, while Gram-negative bacteria have an outer membrane that restricts penicillin entry.

Question 6

Which of the following equations best represents the net movement of water during osmosis across a selectively permeable membrane?

Accepted Answer

$$	ext{Water moves from an area of low solute concentration to an area of high solute concentration}$$

Question 7

Which bacterial structure is primarily responsible for motility in most swimming bacteria?

Accepted Answer

Flagella

Question 8

A bacterium is observed to have a flexible, corkscrew shape and moves using an axial filament. Which group does it most likely belong to?

Accepted Answer

Spirochetes

Question 9

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

Accepted Answer

It aids in attachment to surfaces and evasion of the immune system.

Question 10

Which of the following statements about Gram-negative cell walls is correct?

Accepted Answer

They contain lipopolysaccharides in their outer membrane, which can act as endotoxins.

Question 11

Which of the following best explains why Mycobacterium tuberculosis requires an acid-fast stain rather than a Gram stain for identification?

Accepted Answer

Its cell wall contains mycolic acid, a waxy lipid that resists Gram staining.

Question 12

Which of the following is a function of the bacterial plasma membrane?

Accepted Answer

It is the site of ATP synthesis and acts as a selective permeability barrier.

Question 13

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

Accepted Answer

The cell will shrink due to water loss (plasmolysis).

Question 14

Which of the following best describes the arrangement of peptidoglycan in bacterial cell walls?

Accepted Answer

It is a rigid matrix composed of repeating units of N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) linked by glycosidic bonds and cross-linked by short peptides.

Question 15

Which of the following is a real-world example of group translocation in prokaryotes?

Accepted Answer

The transport of glucose into the cell, where it is phosphorylated to glucose-6-phosphate during entry.

Question 16

Which of the following best explains why lysozyme is effective against many bacteria?

Accepted Answer

It breaks the glycosidic bonds between NAG and NAM in peptidoglycan, weakening the cell wall.

Question 17

Which of the following is a correct statement about endospores?

Accepted Answer

They are dormant, highly resistant structures formed by some bacteria in response to adverse conditions.

Question 18

Which of the following best describes the function of fimbriae in bacteria?

Accepted Answer

They are short, numerous protein structures used for adhesion to surfaces.

Question 19

A bacterial cell is observed to have a tuft of flagella at one end. What is the correct term for this arrangement?

Accepted Answer

Lophotrichous

Question 20

Which of the following best explains why Archaea are naturally resistant to penicillin?

Accepted Answer

They lack peptidoglycan in their cell walls, so penicillin has no target.

Prokaryotic Cells: Structure, Function, and Morphology – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard