Question 1

Which cellular organelle is the primary site of ATP production?

Accepted Answer

The mitochondrion is known as the powerhouse of the cell because it is responsible for producing ATP, the molecule that provides energy for cellular processes. Ribosomes are involved in protein synthesis, the cytoplasm is the fluid in which cellular organelles are suspended, and the endoplasmic reticulum is involved in protein and lipid synthesis and transport.

Question 2

The catabolism of glucose occurs in which cellular compartment?

Accepted Answer

The catabolism of glucose, specifically glycolysis, occurs in the cytoplasm of the cell.

Question 3

Which reaction represents dephosphorylation?

Accepted Answer

Dephosphorylation is the process of removing a phosphate group from a molecule. In choice A, ATP (adenosine triphosphate) is converted to ADP (adenosine diphosphate) and a phosphate group, which represents the removal of a phosphate group from ATP, hence dephosphorylation.

Question 4

The primary high energy molecule in human metabolism is:

Accepted Answer

Adenosine triphosphate (ATP) is the primary molecule for storing and transferring energy in cells, making it crucial for human metabolism.

Question 5

What is the net production of ATP in anaerobic glycolysis from one glucose molecule?

Accepted Answer

Anaerobic glycolysis from one glucose molecule results in a net production of 2 ATP molecules.

Question 6

The coenzyme flavin adenine dinucleotide is derived from a:

Accepted Answer

Flavin adenine dinucleotide (FAD) is derived from riboflavin, which is a B vitamin (specifically, vitamin B2).

Question 7

When oxygen is plentiful, pyruvate from glucose is converted to:

Accepted Answer

When oxygen is plentiful, pyruvate from glucose is primarily converted to acetyl CoA, which then enters the citric acid cycle (Krebs cycle) for further energy production.

Question 8

The production of energy from carbohydrates through oxidation-reduction reactions ultimately yields:

Accepted Answer

The production of energy from carbohydrates through oxidation-reduction reactions in the body (such as in cellular respiration) ultimately yields water (H2O) and carbon dioxide (CO2) as waste products.

Question 9

The process of making large molecules from smaller ones is termed:

Accepted Answer

Anabolism refers to the process of making larger, complex molecules from smaller ones, which is crucial for growth, repair, and maintenance in living organisms.

Question 10

At the end of glycolysis, glucose has been catabolized to form two molecules of:

Accepted Answer

At the end of glycolysis, one molecule of glucose is broken down into two molecules of pyruvate.

Question 11

The first step of glycolysis is:

Accepted Answer

The first step of glycolysis involves the phosphorylation of glucose to glucose-6-phosphate, which is catalyzed by the enzyme hexokinase. This step is crucial for trapping glucose within the cell and preparing it for further metabolism.

Question 12

Which of the following coenzymes is associated with greatest ATP production?

Accepted Answer

Nicotinamide adenine dinucleotide (NAD+) is a coenzyme that plays a crucial role in the production of ATP through its involvement in the electron transport chain, where it is reduced to NADH, contributing significantly to ATP generation.

Question 13

Lactose is formed by which classification of reaction?

Accepted Answer

Lactose is formed by a condensation reaction, where two monosaccharides (glucose and galactose) join together, releasing a molecule of water in the process.

Question 14

The process of breaking down large molecules to release energy is termed:

Accepted Answer

Catabolism refers to the metabolic pathways that break down molecules into smaller units, releasing energy in the process.

Question 15

________ is an anabolic reaction in which water is released as a by-product.

Accepted Answer

Condensation reactions are anabolic processes that combine two or more molecules to form a larger molecule, releasing water as a by-product. This is in contrast to hydrolysis, which breaks down molecules by adding water.

Question 16

The breakdown of maltose into two monosaccharides occurs through a ________ reaction.

Accepted Answer

Hydrolysis is the chemical process that uses water to break down compounds, including the breakdown of maltose into two glucose molecules.

Question 17

Which of the following cells must rely on anaerobic metabolism for ATP production?

Accepted Answer

Red blood cells must rely on anaerobic metabolism for ATP production because they lack mitochondria, which are required for aerobic respiration.

Question 18

Which of the following coenzymes is capable of an oxidation-reduction reaction?

Accepted Answer

Flavin adenine dinucleotide (FAD) is a coenzyme involved in redox (reduction-oxidation) reactions in metabolism. It can accept electrons (reduced) and donate electrons (oxidized), making it capable of participating in oxidation-reduction reactions.

Question 19

A molecule that gives up electrons is:

Accepted Answer

A molecule that gives up electrons is undergoing oxidation, which is defined as the loss of electrons. Therefore, the correct answer is C, oxidized.

Question 20

In the absence of oxygen, glucose is catabolized to:

Accepted Answer

In the absence of oxygen, glucose is catabolized to lactic acid through a process known as anaerobic glycolysis.

Quiz 7: Metabolism: From Food to Life