Question 1

Which of the following best explains why carbon is the backbone of biological molecules?

Accepted Answer

Carbon forms 4 covalent bonds, allowing for versatile structures such as straight chains, branching, and rings.

Question 2

A dehydration reaction in the synthesis of macromolecules involves which of the following?

Accepted Answer

Removing water to form a bond between monomers.

Question 3

Which carbohydrate is primarily used for energy storage in animal cells and is highly branched?

Accepted Answer

Glycogen

Question 4

Which of the following is a correct match between a lipid type and its function?

Accepted Answer

Triglycerides: long-term energy storage

Question 5

A protein’s tertiary structure is primarily stabilized by which type of interaction?

Accepted Answer

Interactions between R groups (side chains)

Question 6

Which statement best describes the central dogma of molecular biology?

Accepted Answer

DNA is transcribed into RNA, which is translated into protein.

Question 7

Which of the following membrane transport mechanisms requires energy in the form of ATP?

Accepted Answer

Active transport via pumps

Question 8

A red blood cell placed in a hypertonic solution will undergo which process?

Accepted Answer

Water will leave the cell, causing it to shrink (plasmolysis).

Question 9

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

Accepted Answer

A dynamic bilayer of phospholipids with embedded proteins and carbohydrates.

Question 10

Which of the following is a function of membrane carbohydrates?

Accepted Answer

Cell-cell recognition, such as blood type identification

Question 11

Which of the following statements about phospholipids is correct?

Accepted Answer

They form a bilayer with hydrophilic heads facing outward and hydrophobic tails facing inward.

Question 12

Which process involves the fusion of vesicles with the plasma membrane to release their contents outside the cell?

Accepted Answer

Exocytosis

Question 13

Which of the following best explains why unsaturated fatty acids increase membrane fluidity?

Accepted Answer

They contain double bonds that create kinks, preventing tight packing.

Question 14

Which of the following is true regarding the structure of nucleic acids?

Accepted Answer

RNA is typically single-stranded and contains the base uracil.

Question 15

A mutation in the gene encoding the CFTR protein affects which membrane transport process, leading to cystic fibrosis?

Accepted Answer

Facilitated diffusion of chloride ions

Question 16

Which of the following equations correctly represents the hydrolysis of a disaccharide?

Accepted Answer

$$C_{12}H$$_{22}$$O_{11} + H$$_{2}$$O \rightarrow 2C_{6}H$$_{12}$$O_{6}$

Question 17

Which of the following best describes the role of integral membrane proteins?

Accepted Answer

They penetrate the hydrophobic core of the lipid bilayer, often spanning the membrane.

Question 18

Which of the following is a correct comparison between DNA and RNA?

Accepted Answer

DNA is double-stranded, while RNA is usually single-stranded.

Question 19

Which of the following scenarios would result in plasmolysis in a plant cell?

Accepted Answer

Placing the cell in a hypertonic solution

Question 20

Which of the following is a correct statement about the relationship between protein sequence and function?

Accepted Answer

The sequence of amino acids determines the protein’s structure, which in turn determines its function.

Biological Molecules and Membrane Structure: Core Concepts in General Biology

Study Guide - Practice Questions