Question 1

Which of the following best describes the difference between covalent and hydrogen bonds in biological molecules?

Accepted Answer

Covalent bonds involve the sharing of electron pairs between atoms, whereas hydrogen bonds are weak attractions between a hydrogen atom and an electronegative atom such as oxygen or nitrogen.

Question 2

A scientist is studying the effect of temperature on enzyme activity. Which step of the scientific method is she performing when she formulates a possible explanation for her observations?

Accepted Answer

Hypothesis formation

Question 3

Which of the following is a property of water that is critical for life and is primarily due to hydrogen bonding?

Accepted Answer

High specific heat capacity

Question 4

Which equation correctly represents the dissociation of water into ions?

Accepted Answer

$$H_2O \rightarrow H^+ + OH^-$$

Question 5

Which of the following best explains why saturated fatty acids tend to be solid at room temperature?

Accepted Answer

Their straight chains allow them to pack closely together, increasing intermolecular forces.

Question 6

A patient is diagnosed with a genetic disorder that affects the folding of proteins. Which level of protein structure is most directly impacted?

Accepted Answer

Tertiary structure

Question 7

Which of the following statements about the sodium-potassium pump is correct?

Accepted Answer

It uses energy from ATP to move sodium ions out of the cell and potassium ions into the cell, establishing an electrochemical gradient.

Question 8

Which of the following best describes the difference between simple diffusion and facilitated diffusion?

Accepted Answer

Facilitated diffusion involves transport proteins, while simple diffusion does not.

Question 9

Which of the following is NOT a function of carbohydrates in living systems?

Accepted Answer

Catalyzing chemical reactions

Question 10

Which of the following best explains the difference between starch and cellulose?

Accepted Answer

Starch is used for energy storage in plants, while cellulose provides structural support in plant cell walls.

Question 11

Which of the following is a correct description of a phospholipid's structure?

Accepted Answer

A hydrophilic head and two hydrophobic tails

Question 12

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

Accepted Answer

Primary structure

Question 13

Which of the following best describes the role of cholesterol in animal cell membranes?

Accepted Answer

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

Question 14

Which of the following is a correct example of a dehydration synthesis reaction?

Accepted Answer

Joining two amino acids to form a dipeptide and releasing a water molecule

Question 15

Which of the following best explains why proteins denature at high temperatures?

Accepted Answer

High temperatures disrupt hydrogen bonds and other interactions responsible for secondary and tertiary structures.

Question 16

Which of the following is a correct comparison between triglycerides and phospholipids?

Accepted Answer

Triglycerides have three fatty acid tails, while phospholipids have two.

Question 17

Which of the following is a correct prediction about the solubility of amino acids in water?

Accepted Answer

Amino acids with polar or charged side chains are more soluble in water due to their ability to form hydrogen bonds.

Question 18

Which of the following best describes the function of carrier proteins in cell membranes?

Accepted Answer

They facilitate the movement of specific molecules across the membrane by changing shape.

Question 19

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

Accepted Answer

Loss of proper folding (denaturation) leads to loss of protein function.

Question 20

Which of the following is a correct prediction about the movement of water across a cell membrane in a hypotonic solution?

Accepted Answer

Water will move into the cell, causing it to swell.

General Biology: Structure and Function of Biomolecules and Cell Transport

Guida di studio - Domande di pratica

Study guide - Flashcard