Question 1

Which of the following functional groups is most likely to be found in the active site of an enzyme that catalyzes phosphorylation reactions?

Accepted Answer

Phosphate group

Question 2

Which type of bond is primarily responsible for the formation of the primary structure of proteins?

Accepted Answer

Peptide bonds

Question 3

A mutation causes a cell to produce phospholipids with two saturated fatty acid tails instead of one saturated and one unsaturated. What is the most likely effect on the plasma membrane?

Accepted Answer

The membrane will become less fluid and more rigid.

Question 4

Which of the following best describes the amphipathic nature of phospholipids?

Accepted Answer

They have both hydrophilic and hydrophobic regions.

Question 5

Which class of macromolecule is NOT formed by dehydration synthesis?

Accepted Answer

Lipids

Question 6

A scientist uses FRAP (Fluorescence Recovery After Photobleaching) to study membrane fluidity. Which result would indicate a highly fluid membrane?

Accepted Answer

Rapid recovery of fluorescence in the bleached area

Question 7

Which of the following statements about the Fluid Mosaic Model is correct?

Accepted Answer

Phospholipids and proteins can move laterally within the layer.

Question 8

Which of the following changes would most likely increase the fluidity of a cell membrane at low temperatures?

Accepted Answer

Increasing the proportion of unsaturated fatty acids

Question 9

Which of the following is a function of glycoproteins in the plasma membrane?

Accepted Answer

Cell-cell recognition

Question 10

A cell is placed in a solution and water moves into the cell. Which type of solution is the cell in?

Accepted Answer

Hypotonic

Question 11

Which of the following best explains why cholesterol is important for membrane fluidity?

Accepted Answer

It prevents the membrane from solidifying at low temperatures.

Question 12

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

Accepted Answer

Energy storage

Question 13

Which of the following statements about integral membrane proteins is correct?

Accepted Answer

They span the lipid bilayer and have hydrophobic regions.

Question 14

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

Accepted Answer

They are involved in cell recognition and signaling.

Question 15

A researcher observes that a certain protein can move laterally within the membrane but cannot flip-flop to the other side. What property of the membrane does this illustrate?

Accepted Answer

Membrane asymmetry

Question 16

Which of the following would most likely decrease the rate of lateral diffusion of phospholipids in a membrane?

Accepted Answer

Increasing the proportion of saturated fatty acids

Question 17

Which of the following is a characteristic of the quaternary structure of proteins?

Accepted Answer

It describes the arrangement of multiple polypeptide subunits.

Question 18

Which of the following best explains why membrane proteins are amphipathic?

Accepted Answer

They contain both hydrophilic and hydrophobic amino acid residues.

Question 19

Which of the following experimental techniques is used to study the mobility of membrane proteins?

Accepted Answer

FRAP (Fluorescence Recovery After Photobleaching)

Question 20

Which of the following statements about the permeability of biological membranes is correct?

Accepted Answer

Small nonpolar molecules can diffuse freely across the membrane.

Cell Membranes: Structure, Function, and Chemistry

Guida di studio - Domande di pratica

Study guide - Flashcard