Question 1

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

Accepted Answer

A flexible layer made of phospholipids with proteins embedded throughout, allowing for dynamic movement and various functions.

Question 2

A patient with hypercholesterolemia has high levels of LDL in their blood because:

Accepted Answer

LDLs cannot enter cells via receptor-mediated endocytosis, causing accumulation in the blood.

Question 3

Which of the following molecules would most easily diffuse through the plasma membrane without assistance?

Accepted Answer

Oxygen ($$O_2)$$

Question 4

A red blood cell is placed in a hypotonic solution. What will happen to the cell and why?

Accepted Answer

It will swell and possibly burst because water enters the cell due to osmosis.

Question 5

Which organelle is responsible for producing the majority of ATP in a cell during aerobic respiration?

Accepted Answer

Mitochondrion

Question 6

A cell is observed to have abundant smooth endoplasmic reticulum. Which function is this cell likely specialized for?

Accepted Answer

Lipid metabolism and detoxification

Question 7

Which of the following best explains why facilitated diffusion exhibits saturation kinetics?

Accepted Answer

All available transport proteins become occupied, limiting the rate of transport.

Question 8

Which of the following cell junctions would you expect to find in tissues that require a strong, flexible connection, such as cardiac muscle?

Accepted Answer

Desmosomes

Question 9

A cell is actively transporting sodium ions ($$Na^+) $$out of the cell against their concentration gradient. Which of the following is true about this process?

Accepted Answer

It requires ATP and is an example of active transport.

Question 10

Which organelle is most directly involved in the modification, packaging, and sorting of proteins for secretion?

Accepted Answer

Golgi apparatus

Question 11

Which cytoskeletal element is primarily responsible for muscle contraction and cell division?

Accepted Answer

Microfilaments

Question 12

A cell is observed to engulf a bacterium by surrounding it with its plasma membrane and forming a vesicle. This process is best described as:

Accepted Answer

Phagocytosis

Question 13

Which of the following statements about osmosis is correct?

Accepted Answer

Osmosis is the passive movement of water through aquaporins, following solute concentration.

Question 14

Which of the following best describes the role of cholesterol in the plasma membrane?

Accepted Answer

It stabilizes the membrane and adjusts its flexibility.

Question 15

A cell with defective lysosomes would have difficulty with which of the following processes?

Accepted Answer

Breaking down macromolecules and cellular debris

Question 16

Which of the following is a function of integral membrane proteins?

Accepted Answer

Acting as enzymes, transport channels, receptors, and anchors

Question 17

A cell is placed in a hypertonic solution. Predict what will happen and explain why.

Accepted Answer

Water will leave the cell, causing it to shrink due to osmosis.

Question 18

Which of the following best explains why mitochondria are often called the 'powerhouse' of the cell?

Accepted Answer

They generate ATP through aerobic respiration, providing energy for cellular activities.

Question 19

Which of the following is NOT a function of the cytoskeleton?

Accepted Answer

Synthesizing DNA

Question 20

Which of the following best describes the process of exocytosis?

Accepted Answer

The cell expels molecules by fusing vesicles with the plasma membrane.

Cell Structure and Function: Mini-Textbook Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards