Question 1

Which of the following best describes the role of the sodium-potassium pump in maintaining cell membrane potential?

Accepted Answer

It actively transports sodium ions out of the cell and potassium ions into the cell, using ATP.

Question 2

A neuron receives a signal that causes sodium channels to open. What is the immediate effect on the membrane potential?

Accepted Answer

The membrane potential becomes less negative, leading to depolarization.

Question 3

Which equation correctly represents the free energy change ($$\Delta G) $$for a chemical reaction?

Accepted Answer

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

Question 4

During cellular respiration, which process directly produces the most ATP per glucose molecule?

Accepted Answer

Electron transport chain and oxidative phosphorylation

Question 5

Which organelle is primarily responsible for ATP production in eukaryotic cells?

Accepted Answer

Mitochondrion

Question 6

A patient is diagnosed with a defect in the enzyme hexokinase. Which step of cellular respiration is most directly affected?

Accepted Answer

Phosphorylation of glucose in glycolysis

Question 7

Which of the following statements about facilitated diffusion is correct?

Accepted Answer

It uses membrane proteins to transport molecules down their concentration gradient.

Question 8

Which hormone is released by the adrenal medulla in response to stress, and what is its primary effect?

Accepted Answer

Epinephrine; increases heart rate and blood glucose levels

Question 9

Which of the following best explains why ATP is considered the 'energy currency' of the cell?

Accepted Answer

ATP contains high-energy phosphate bonds that can be hydrolyzed to release energy for cellular work.

Question 10

Which of the following is a correct sequence of events in the signal transduction pathway involving a G protein-coupled receptor?

Accepted Answer

Ligand binds receptor → G protein activated → second messenger produced → cellular response

Question 11

Which of the following best describes the function of the hypothalamus in endocrine signaling?

Accepted Answer

It acts as a relay center, integrating signals from the nervous system and controlling the pituitary gland.

Question 12

Which of the following is a correct description of the role of NADH in cellular respiration?

Accepted Answer

NADH donates electrons to the electron transport chain, facilitating ATP production.

Question 13

Which of the following equations represents the net ATP yield from one molecule of glucose during aerobic cellular respiration?

Accepted Answer

$$C_6H_{12}O_6$ + 6O_2 \rightarrow 6CO_2 + 6H_2O + 36-38\ ATP$$

Question 14

A mutation causes the loss of function of the enzyme phosphofructokinase in a cell. What is the most likely consequence?

Accepted Answer

Glycolysis is inhibited, reducing ATP production.

Question 15

Which of the following best explains the difference between anabolic and catabolic pathways?

Accepted Answer

Anabolic pathways build complex molecules using energy, while catabolic pathways break down molecules to release energy.

Question 16

Which of the following is an example of a negative feedback mechanism in endocrine regulation?

Accepted Answer

High blood glucose stimulates insulin release, which lowers blood glucose.

Question 17

Which of the following statements about the citric acid cycle is correct?

Accepted Answer

It produces NADH, FADH2, and CO2 as major products.

Question 18

A person is unable to produce insulin. Which process is most directly affected?

Accepted Answer

Regulation of blood glucose levels

Question 19

Which of the following best describes the evolutionary adaptation of vertebrate digestive systems to diet?

Accepted Answer

Herbivores have longer intestines to maximize nutrient absorption from plant material.

General Biology: Study Guide on Membrane Transport, Cell Signaling, Metabolism, Cellular Respiration, and Animal Nutrition

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