Question 1

Which of the following is NOT considered one of the fundamental properties of life?

Accepted Answer

The ability to exist indefinitely without any energy input from the environment

Question 2

A student learns that rod cells in the retina are much more numerous than cone cells and contain a special protein called rhodopsin that can detect even single photons of light. However, rod cells cannot distinguish between different colors. Based on this structural information, when would rod cells be most functionally important?

Accepted Answer

When navigating in dim moonlight or a dark room

Question 3

Most water molecules in ice form ______ hydrogen bonds. That is why ice is ______ dense than water.

Accepted Answer

4, less

Question 4

Carbonic acid/bicarbonate is the main buffer in human blood. It contributes to maintaining the blood pH constant around 7.4. If the pH in the blood unexpectedly rises to 7.8, the above equilibrium will move to the right or to the left?

Accepted Answer

LEFT

Question 5

The ability of water molecules to form hydrogen bonds gives rise to several important properties associated with liquid water. Water molecules can form a ______ surrounding a hydrophilic molecule, but do not interact with molecules where ______ bonds predominate.

Accepted Answer

Hydration shell, non-polar covalent

Question 6

Which of the following functional groups is regularly found in carbohydrates?

Accepted Answer

A and B

Question 7

Which functional group is an important component of fatty acids?

Accepted Answer

F

Question 8

A glycosidic linkage is a ______ bond between ______.

Accepted Answer

Covalent, monosaccharides

Question 9

The molecule cholesterol contains a carbon skeleton with ______ carbon ring(s) and is a major component of the ______. It is also the precursor for the synthesis of ______.

Accepted Answer

4, cell membrane, testosterone

Question 10

Establishing a diffusion barrier against charged molecules in the plasma membrane would likely be impaired in which function?

Accepted Answer

Establishing a diffusion barrier against charged molecules

Question 11

Which of these molecules is called an acid because it loses an H+ in a cellular aqueous solution?

Accepted Answer

F

Question 12

Even a slight change in primary structure can affect a protein’s conformation and ability to function. In sickle cell anemia, a single ______ change in DNA leads to a single ______ change in the polypeptide, and ultimately affects ______ protein structure.

Accepted Answer

Nucleotide, amino acid, tertiary

Question 13

Alterations in pH, salt concentration, temperature, or other factors can denature a protein. Some proteins can return to their functional shape after denaturation, but others cannot. A mutation in chaperone proteins that impairs chaperone function would lead to:

Accepted Answer

The accumulation of denatured proteins in the cell

Question 14

Cholesterol travels in the blood in low-density lipoproteins (LDL) complexes of protein and lipids. In familial hypercholesterolemia, an inherited disease, the patients suffer an accumulation of LDL cholesterol in the blood. This contributes to early atherosclerosis. What is a common cause of familial hypercholesterolemia?

Accepted Answer

Defective receptor-mediated endocytosis

Question 15

The Na+/K+ pump is the main electrogenic pump in animal cells. A mutation affecting the Na+/K+ pump’s ability to use ATP will likely lead to:

Accepted Answer

A change in the voltage gradient across the cell membrane

Question 16

Aquaporin channels do not require energy to mediate the transport of water molecules in and out of the cell. True or False?

Accepted Answer

True

Question 17

The above experiment proved the lateral drift of membrane proteins, giving support to the fluid mosaic model. If we increase the percentage of phospholipids with unsaturated hydrophobic tails in the membrane of both cells and perform the experiment again, we should expect:

Accepted Answer

A faster lateral drift of both mouse and human proteins

Question 18

Cytochalasin D is a drug that prevents actin polymerization. Which of the following processes will be most affected in cells treated with cytochalasin D?

Accepted Answer

White blood cell motility

Question 19

The liver is involved in detoxification of many poisons and drugs. Which of the following structures is abundant in liver cells and primarily responsible for detoxification processes?

Accepted Answer

Smooth endoplasmic reticulum

Question 20

Which of the following signal transduction proteins typically functions by forming dimers after binding to a signal molecule?

Accepted Answer

Receptor tyrosine kinases

General Biology: Cell Structure, Membrane Function, and Biochemistry Study Guide

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