$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} \rightarrow \mathrm{ADP} + \mathrm{P}_i + \text{energy}$

Question 1

Which of the following best describes the role of hydrogen bonds in the structure of DNA?

Accepted Answer

They stabilize the double helix by connecting complementary nitrogenous bases.

Question 2

A mutation causes a change in the primary structure of a protein. Which level of protein structure is directly affected first?

Accepted Answer

Primary structure

Question 3

Which of the following best explains why sickle cell anemia results from a single amino acid substitution in hemoglobin?

Accepted Answer

The substitution alters the primary structure, which changes the protein's folding and function.

Question 4

Which of the following equations correctly represents the energy released from ATP hydrolysis?

Accepted Answer

$\mathrm{ATP} + \mathrm{H}_2\mathrm{O} ightarrow \mathrm{ADP} + \mathrm{P}_i + 	ext{energy}$

Question 5

Which of the following is a difference between DNA and RNA?

Accepted Answer

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

Question 6

A cell is placed in a hypertonic solution. What will happen to the cell?

Accepted Answer

Water will leave the cell, causing it to shrink.

Question 7

Which of the following best describes the function of the sodium-potassium pump?

Accepted Answer

It uses ATP to move sodium out of the cell and potassium into the cell.

Question 8

Which of the following is a correct pairing of a purine and a pyrimidine in DNA?

Accepted Answer

Adenine and thymine

Question 9

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

Accepted Answer

A double layer of phospholipids with proteins floating within and on the layer

Question 10

Which of the following processes requires energy input in the form of ATP?

Accepted Answer

Primary active transport

Question 11

During transcription, which enzyme is responsible for synthesizing RNA from a DNA template?

Accepted Answer

RNA polymerase

Question 12

Which of the following is a function of the rough endoplasmic reticulum (ER)?

Accepted Answer

Protein synthesis for secretion

Question 13

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

Accepted Answer

It increases membrane fluidity at high temperatures and decreases it at low temperatures.

Question 14

Which of the following is a common mistake when translating mRNA into a protein sequence?

Accepted Answer

Counting codons (mRNA) with anticodons (tRNA) when obtaining a sequence

Question 15

Which of the following best describes facilitated diffusion?

Accepted Answer

Movement of molecules from high to low concentration through a protein channel

Question 16

Which of the following is true about the directionality of DNA synthesis?

Accepted Answer

DNA is synthesized in the 5' to 3' direction.

Question 17

Which of the following organelles is responsible for packaging and modifying proteins for secretion?

Accepted Answer

Golgi apparatus

Question 18

Which of the following best describes osmosis?

Accepted Answer

Movement of water from low solute concentration to high solute concentration across a semipermeable membrane

Question 19

Which of the following is a function of lysosomes?

Accepted Answer

Digestion of cellular waste

Question 20

Which of the following is a correct statement about secondary active transport (symport)?

Accepted Answer

It uses the energy from the movement of one molecule down its gradient to move another molecule against its gradient.

SCB-203 Exam 2 Review: Molecular and Cellular Foundations

Study Guide - Practice Questions