Biology Test Biology Cell Structure & Function 3

Question 1

A cell placed in a hypertonic solution will most likely:

Accepted Answer

Shrink due to water loss by osmosis

Answer

Swell and potentially burst

Answer

Remain unchanged because concentration is equal

Answer

Actively pump solutes outward

Question 2

Which of the following best describes the fluid mosaic model of the plasma membrane?

Accepted Answer

A dynamic phospholipid bilayer with mobile embedded proteins and cholesterol

Answer

A rigid lattice of proteins embedded in a solid lipid layer

Answer

A single layer of phospholipids with proteins only on the outer surface

Answer

A carbohydrate matrix supported by a protein scaffold

Question 3

What happens to a plant cell in a hypotonic solution?

Accepted Answer

It becomes turgid as water enters but is restrained by the cell wall

Answer

It lyses because it lacks a cell wall

Answer

It undergoes plasmolysis

Answer

It loses chlorophyll

Question 4

Which protein channel facilitates the passive transport of water across the cell membrane?

Accepted Answer

Aquaporins

Answer

Ion channels

Answer

ATP-binding cassette transporters

Answer

Carrier proteins

Question 5

During endocytosis, a cell engulfs a large solid particle by extending pseudopods around it. This specific process is called:

Accepted Answer

Phagocytosis

Answer

Pinocytosis

Answer

Exocytosis

Answer

Receptor-mediated endocytosis

Question 6

The sodium-potassium pump maintains the resting membrane potential by:

Accepted Answer

Moving 3 Na⁺ out and 2 K⁺ in per cycle using ATP

Answer

Moving 2 Na⁺ out and 3 K⁺ in per cycle

Answer

Allowing Na⁺ and K⁺ to diffuse freely down concentration gradients

Answer

Pumping Na⁺ and K⁺ in equal amounts in the same direction

Question 7

Gap junctions in animal cells primarily allow:

Accepted Answer

Direct cytoplasmic communication between neighboring cells

Answer

Structural support between adjacent cells

Answer

Passage of large proteins between cells

Answer

Immune recognition of self vs. non-self