Question 1

Why are cells generally small in size? Which of the following best explains the biological significance of the surface area to volume ratio in cells?

Accepted Answer

Smaller cells have a higher surface area to volume ratio, which allows for more efficient exchange of materials with their environment.

Question 2

Which of the following statements is NOT part of the modern cell theory?

Accepted Answer

All cells contain a nucleus to store genetic material.

Question 3

Which scientist is correctly matched with their contribution to cell theory?

Accepted Answer

Virchow – Stated that all cells arise from pre-existing cells.

Question 4

Which of the following structures is found in both Bacteria and Archaea but NOT in Eukaryotic cells?

Accepted Answer

Nucleoid region

Question 5

A bacterium is observed to have fimbriae, a nucleoid, and a cell wall. Which of the following is a function of fimbriae?

Accepted Answer

Attachment to surfaces or other cells

Question 6

Which of the following best describes the endosymbiotic hypothesis for the origin of mitochondria and chloroplasts?

Accepted Answer

They originated as free-living prokaryotes that were engulfed by ancestral eukaryotic cells.

Question 7

Which of the following organelles is NOT part of the endomembrane system?

Accepted Answer

Mitochondrion

Question 8

According to the fluid-mosaic model, which statement best describes the structure of the plasma membrane?

Accepted Answer

A dynamic bilayer of phospholipids with proteins and other molecules embedded throughout.

Question 9

What is the primary role of cholesterol in the plasma membrane of animal cells?

Accepted Answer

To maintain membrane fluidity across temperature changes

Question 10

Which of the following best describes facilitated diffusion?

Accepted Answer

Movement of molecules down their concentration gradient through a membrane protein, without energy input

Question 11

A red blood cell is placed in a solution and begins to shrink. Which term best describes the tonicity of the solution relative to the cell?

Accepted Answer

Hypertonic

Question 12

Which equation correctly represents water potential ($$\Psi) in $$plant cells?

Accepted Answer

$$\Psi = \Psi_s + \Psi_p$$

Question 13

A plant cell is placed in a solution with a higher water potential than the cell's interior. What will most likely happen to the cell?

Accepted Answer

It will become turgid as water enters the cell.

Question 14

Which process involves the engulfment of large particles by the cell membrane to form an internal vesicle?

Accepted Answer

Phagocytosis

Question 15

A cell uses ATP to pump sodium ions out of the cell against their concentration gradient. This is an example of:

Accepted Answer

Active transport

Question 16

Which of the following best explains why plant cells do not burst when placed in a hypotonic solution?

Accepted Answer

The cell wall provides structural support and prevents excessive expansion.

Question 17

Which of the following is a correct description of the role of membrane carbohydrates?

Accepted Answer

They function in cell recognition and signaling.

Question 18

A freshwater protozoan is transferred to seawater. What will most likely happen to the protozoan, and why?

Accepted Answer

It will lose water and shrink due to osmosis.

Question 19

Which of the following best describes the difference between pinocytosis and phagocytosis?

Accepted Answer

Pinocytosis involves the uptake of liquids, while phagocytosis involves the uptake of large particles.

Question 20

A scientist measures the solute potential ($$\Psi_s) of a $$plant cell as $$-0.7$$ MPa and the pressure potential ($$\Psi_p) as$$ $$0.5$$ MPa. What is the total water potential ($$\Psi) of $$the cell?

Accepted Answer

$$\Psi = -0.2$$ MPa

Cell Structure, Membranes, and Transport: Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard