Question 1

A patient is given an intravenous solution that is hypotonic relative to their red blood cells. What is the most likely outcome for the red blood cells, and which process is primarily responsible?

Accepted Answer

They will burst due to osmosis moving water into the cells.

Question 2

Which of the following best describes the function of the sodium-potassium pump in maintaining membrane potential?

Accepted Answer

It actively transports sodium ions out of the cell and potassium ions into the cell, using ATP.

Question 3

A scientist observes that a certain molecule moves across the cell membrane from high to low concentration without the use of energy, but only when a specific protein is present. Which transport mechanism is being observed?

Accepted Answer

Facilitated diffusion

Question 4

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

Accepted Answer

$$J = -P (C_2$ - C_1$)$$

Question 5

A cell is placed in a solution and begins to swell. Which of the following best explains this observation?

Accepted Answer

The solution is hypotonic, causing water to enter the cell by osmosis.

Question 6

Which of the following statements about vesicular transport is correct?

Accepted Answer

It requires ATP and is used to move large substances across the membrane.

Question 7

During phagocytosis, which sequence of events occurs as a white blood cell engulfs a bacterium?

Accepted Answer

The bacterium binds to a receptor, the membrane forms a vesicle, and lysosomes digest the bacterium.

Question 8

Which of the following best explains why the sodium-potassium pump is considered an example of active transport?

Accepted Answer

It requires ATP to move ions against their concentration gradients.

Question 9

A cell lacking functional ribosomes would be unable to:

Accepted Answer

Synthesize proteins from mRNA templates.

Question 10

Which of the following is a key difference between simple diffusion and facilitated diffusion?

Accepted Answer

Facilitated diffusion uses membrane proteins to transport substances that cannot pass directly through the lipid bilayer.

Question 11

Which of the following best describes the role of aquaporin channels in the cell membrane?

Accepted Answer

They facilitate the passive movement of water molecules across the membrane.

Question 12

A neuron has a resting membrane potential of $$-70\ \mathrm{mV}. $$What does this value indicate about the distribution of charge across the plasma membrane?

Accepted Answer

The inside of the cell is more negative than the outside.

Question 13

Which of the following best explains why ATP is required for vesicular transport but not for simple diffusion?

Accepted Answer

Vesicular transport moves substances against their concentration gradient, while simple diffusion moves substances down their gradient.

Question 14

Which of the following scenarios would most likely result in the failure of cellular protein synthesis?

Accepted Answer

A mutation that prevents the formation of mRNA from DNA.

Question 15

Which of the following best describes the function of lysosomes in a cell?

Accepted Answer

They contain digestive enzymes that break down engulfed material and cellular debris.

Question 16

A cell is unable to maintain its concentration gradients of sodium and potassium ions. Which organelle or structure is most likely malfunctioning?

Accepted Answer

Sodium-potassium pump

Question 17

Which of the following is a direct result of exocytosis in pancreatic beta cells?

Accepted Answer

Insulin is released into the bloodstream.

Question 18

Which of the following best explains why the endoplasmic reticulum (ER) is important for protein synthesis?

Accepted Answer

The rough ER provides a site for ribosomes to synthesize proteins that are destined for secretion or membranes.

Question 19

Which of the following best describes the relationship between concentration gradients and passive transport?

Accepted Answer

Passive transport moves substances from high to low concentration, driven by the concentration gradient.

Question 20

A cell is observed to have a large number of mitochondria. Which of the following is the most likely explanation for this observation?

Accepted Answer

The cell requires large amounts of ATP for its functions.

08/21 Lecture Cell Biology Essentials: Membrane Transport, Organelles, and Protein Synthesis

Guida di studio - Domande di pratica

Study guide - Flashcard