Question 1

Which of the following best describes the structure of the plasma membrane in human cells?

Accepted Answer

A double layer of phospholipids with hydrophilic heads facing outward and hydrophobic tails facing inward.

Question 2

Which component of the plasma membrane is primarily responsible for increasing membrane stability?

Accepted Answer

Cholesterol

Question 3

A red blood cell is placed in a hypotonic solution. What is the most likely outcome?

Accepted Answer

The cell will gain water and may burst (lyse).

Question 4

Which of the following best explains why oxygen and carbon dioxide can easily diffuse across the plasma membrane?

Accepted Answer

They are small, nonpolar molecules.

Question 5

Which process requires energy in the form of ATP to move substances against their concentration gradient?

Accepted Answer

Primary active transport

Question 6

The sodium-potassium pump moves ions across the plasma membrane. Which of the following correctly describes this process?

Accepted Answer

$$3 \ \mathrm{Na}^+$$ ions are pumped out and $$2 \ \mathrm{K}^+$$ ions are pumped in, using one ATP.

Question 7

Which of the following is a function of the glycocalyx on the cell surface?

Accepted Answer

Providing specific biological markers for cell-to-cell recognition

Question 8

A patient receives an intravenous solution that is hypertonic relative to their red blood cells. What will happen to the red blood cells?

Accepted Answer

They will shrink due to water loss.

Question 9

Which organelle is responsible for producing most of the ATP in a cell through aerobic metabolism?

Accepted Answer

Mitochondrion

Question 10

Which of the following best describes facilitated diffusion?

Accepted Answer

Movement of molecules down their concentration gradient with the help of carrier proteins, without energy input.

Question 11

Which of the following is NOT a function of the plasma membrane?

Accepted Answer

Synthesis of proteins

Question 12

Which type of membrane transport is used by white blood cells to engulf bacteria?

Accepted Answer

Phagocytosis

Question 13

Which of the following statements about membrane proteins is TRUE?

Accepted Answer

Integral proteins span the membrane and can function as channels or receptors.

Question 14

Which organelle is responsible for the synthesis of steroid hormones and detoxification of drugs?

Accepted Answer

Smooth endoplasmic reticulum

Question 15

A cell is placed in an isotonic solution. What will happen to the cell?

Accepted Answer

It will remain the same size and shape.

Question 16

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

Accepted Answer

They facilitate the rapid diffusion of water across the membrane.

Question 17

Which process involves the packaging of extracellular materials into vesicles for import into the cell, often using specific receptors?

Accepted Answer

Receptor-mediated endocytosis

Question 18

Which cytoskeletal component is primarily responsible for muscle contraction by interacting with myosin?

Accepted Answer

Microfilaments

Question 19

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

Accepted Answer

Breakdown and recycling of damaged organelles and pathogens

Question 20

Which of the following is a correct description of the genetic code in the nucleus?

Accepted Answer

It is a sequence of three DNA bases (triplet code) that codes for one amino acid.

Cell Structure and Membrane Transport: Foundations for GOB Chemistry

Guida di studio - Domande di pratica