Question 1

Which of the following best describes the role of the control group in a double-blind clinical trial testing a new medication?

Accepted Answer

It receives a placebo to serve as a baseline for comparison.

Question 2

A researcher is studying a protein that loses its function when exposed to high temperatures. Which level of protein structure is MOST likely disrupted first, and what type of bond is primarily affected?

Accepted Answer

Secondary structure; hydrogen bonds

Question 3

Which of the following statements about membrane transport is CORRECT?

Accepted Answer

Osmosis is the diffusion of water across a selectively permeable membrane.

Question 4

A solution has a hydrogen ion concentration of $$[H^+] = 1 	imes 10$$^{-5}$$~\mathrm{M}. $$What is its pH?

Accepted Answer

$$pH = 5$$

Question 5

Which of the following best explains why cellulose and starch, both polymers of glucose, have different physical properties?

Accepted Answer

Cellulose has $$\beta-1$$,4 glycosidic linkages, making it unbranched and rigid, while starch has $$\alpha-1$$,4 and $$\alpha-1$$,6 linkages, making it branched and flexible.

Question 6

During aerobic cellular respiration, what is the role of oxygen in the electron transport chain?

Accepted Answer

It serves as the final electron acceptor, forming water.

Question 7

Which of the following scenarios illustrates feedback inhibition in a metabolic pathway?

Accepted Answer

The final product of a pathway binds to an enzyme early in the pathway, decreasing its activity.

Question 8

A mutation in a gene results in a protein with a single amino acid change. Which level of protein structure is directly altered by this mutation?

Accepted Answer

Primary structure

Question 9

Which of the following best describes the difference between prokaryotic and eukaryotic transcription?

Accepted Answer

Eukaryotic transcription occurs in the nucleus and includes 5' capping, splicing, and polyadenylation.

Question 10

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

Accepted Answer

It will shrink as water leaves the cell.

Question 11

Which of the following is an example of a catabolic pathway?

Accepted Answer

Breakdown of glucose to pyruvate during glycolysis

Question 12

Which functional group is found in all amino acids and is responsible for their acidic properties?

Accepted Answer

Carboxyl group ($$-COOH)$$

Question 13

A patient is diagnosed with a genetic disorder caused by a defect in a lysosomal enzyme. Which cellular process is most directly affected?

Accepted Answer

Digestion of macromolecules

Question 14

Which of the following best explains why phospholipids form bilayers in water?

Accepted Answer

Their hydrophobic tails avoid water while hydrophilic heads interact with water.

Question 15

Which process increases genetic variation during meiosis?

Accepted Answer

Crossing-over during prophase I

Question 16

A scientist adds a competitive inhibitor to an enzyme-catalyzed reaction. What is the most likely effect?

Accepted Answer

The inhibitor binds to the active site, preventing substrate binding.

Question 17

Which of the following is a correct representation of the Gibbs free energy equation?

Accepted Answer

$$\Delta G = \Delta H - T\Delta S$$

Question 18

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

Accepted Answer

It moves 3 Na$$^+$$ ions out of the cell and 2 K$$^+$$ ions in per ATP hydrolyzed.

Question 19

Which of the following scenarios is an example of gene regulation by negative control in prokaryotes?

Accepted Answer

A repressor protein binds to the operator, blocking RNA polymerase from transcribing the gene.

Question 20

A woman who is heterozygous for a recessive genetic disorder (Aa) and a man who is homozygous dominant (AA) have a child. What is the probability that their child will be a carrier (heterozygous) for the disorder?

Accepted Answer

$$0.5$$

Comprehensive Study Notes for Introductory Biology: Biomolecules, Cell Structure, and Genetics

Study Guide - Practice Questions

Study Guide - Flashcards