Question 1

Which property of living organisms allows them to maintain a stable internal environment despite changes in the external environment?

Accepted Answer

Homeostasis through internal control systems with feedback

Question 2

In the context of energy in biological systems, which statement best describes how animals obtain energy?

Accepted Answer

Animals must import energy through ingestion of plants or other animals

Question 3

Which type of work involves moving ions and molecules to create concentration gradients across membranes?

Accepted Answer

Transport work

Question 4

According to the first law of thermodynamics, which of the following is true?

Accepted Answer

The total amount of energy in the universe is constant

Question 5

Which equation correctly represents a decomposition reaction as described in Table 4.2?

Accepted Answer

$$C \rightarrow A + B$$

Question 6

What is the primary role of enzymes in biological reactions?

Accepted Answer

Enzymes speed up the rate of chemical reactions by lowering activation energy

Question 7

Which of the following best describes an oxidation-reduction reaction?

Accepted Answer

A reaction where electrons are transferred between molecules

Question 8

A patient has elevated blood levels of creatine kinase (CK). Which condition is most likely indicated?

Accepted Answer

Myocardial infarction (heart attack) or muscle disease

Question 9

If the pH of the environment shifts from 7.4 to 6, what happens to the activity of most human enzymes?

Accepted Answer

Enzyme activity decreases

Question 10

Which of the following reactions is catalyzed by kinases?

Accepted Answer

Addition of a phosphate group

Question 11

Which metabolic pathway produces the most ATP from one glucose molecule under aerobic conditions?

Accepted Answer

Electron transport system

Question 12

What is the net ATP yield from anaerobic metabolism of one glucose molecule?

Accepted Answer

2 ATP

Question 13

Which process is an example of feedback inhibition in metabolic pathways?

Accepted Answer

The accumulation of end product Z inhibits the first step of the pathway

Question 14

Which of the following is a correct description of catabolism?

Accepted Answer

Energy-releasing breakdown of molecules

Question 15

Which statement best explains why enzymes are specific to certain reactions?

Accepted Answer

The sequence and number of amino acids in enzymes determine their specificity

Question 16

Which of the following is an example of a ligation reaction?

Accepted Answer

Joining two substrates using energy from ATP

Question 17

Which process describes the conversion of DNA to RNA?

Accepted Answer

Transcription

Question 18

What is the role of alternative splicing in protein synthesis?

Accepted Answer

It allows multiple proteins to be produced from one DNA sequence

Question 19

Which of the following best describes the function of tRNA during translation?

Accepted Answer

tRNA binds to mRNA codon and carries the corresponding amino acid to the peptide chain

Question 20

Which of the following is NOT a way cells regulate their metabolic pathways?

Accepted Answer

Increasing the number of chromosomes

Energy and Cellular Metabolism: Core Concepts in Human Physiology

Study Guide - Practice Questions