Question 1

Which of the following best describes the role of the carbonic acid-bicarbonate buffer system in maintaining blood pH?

Accepted Answer

It maintains blood pH by neutralizing acids and bases through reversible chemical reactions.

Question 2

A patient’s blood pH drops to 7.28. Which physiological response would most likely occur to restore homeostasis?

Accepted Answer

The respiratory rate would increase to expel more CO$_2$ and raise pH.

Question 3

According to Le Chatelier’s Principle, what happens to the equilibrium of the reaction $\mathrm{CO_2 + H_2O \rightleftharpoons H_2CO_3 \rightleftharpoons H^+ + HCO_3^-}$ when blood CO$_2$ levels increase?

Accepted Answer

The equilibrium shifts to produce more bicarbonate ions and hydrogen ions.

Question 4

Which organ systems are primarily responsible for regulating blood pH in the human body?

Accepted Answer

Respiratory and urinary systems

Question 5

If a person is experiencing metabolic acidosis, which of the following compensatory mechanisms is most likely to occur?

Accepted Answer

Increased renal excretion of hydrogen ions

Question 6

What is the formula for calculating pH from hydrogen ion concentration?

Accepted Answer

$\mathrm{pH = -\log_{10}[H^+]}$

Question 7

A blood sample has a hydrogen ion concentration of $1 	imes 10^{-7}$ M. What is the pH of this blood?

Accepted Answer

pH = 7

Question 8

Which of the following symptoms is most likely associated with alkalosis?

Accepted Answer

Muscle fatigue and twitching

Question 9

Why is a pH of 7.0 considered neutral?

Accepted Answer

Because the concentration of $[H^+]$ equals the concentration of $[OH^-]$

Question 10

Which of the following would most likely cause respiratory acidosis?

Accepted Answer

Hypoventilation leading to CO$_2$ retention

Question 11

A patient with chronic kidney disease is unable to excrete hydrogen ions efficiently. What condition are they at risk for developing?

Accepted Answer

Metabolic acidosis

Question 12

Which of the following best explains how buffers help maintain pH in biological systems?

Accepted Answer

Buffers resist changes in pH by reversibly binding or releasing hydrogen ions.

Question 13

If Eugene’s blood pH is 7.28, which of the following best describes his condition?

Accepted Answer

He is experiencing acidosis.

Question 14

Which of the following is a common cause of metabolic alkalosis?

Accepted Answer

Excessive vomiting leading to loss of stomach acid

Question 15

Which feedback loop component detects a change in a physiological variable such as blood pH?

Accepted Answer

Receptor

Question 16

A person is hyperventilating due to anxiety. According to Le Chatelier’s Principle, what effect will this have on their blood pH?

Accepted Answer

Blood pH will increase due to decreased CO$_2$ levels.

Question 17

Which of the following ions is most directly involved in the generation of action potentials in neurons and muscle cells?

Accepted Answer

Sodium ($\mathrm{Na^+}$)

Question 18

Which of the following best describes the effect of low magnesium levels on the body?

Accepted Answer

It can lead to muscle cramps and increased risk of seizures.

Question 19

Which of the following is a direct effect of acidosis on the nervous system?

Accepted Answer

Depression of neural activity leading to lethargy and confusion

Question 20

A patient is administered intravenous bicarbonate to correct acidosis. Which chemical reaction is promoted to help raise blood pH?

Accepted Answer

$\mathrm{H^+ + HCO_3^- \rightarrow H_2CO_3 \rightarrow CO_2 + H_2O}$

Physiology, pH Balance, and Electrolytes: Study Guide for Anatomy & Physiology

Study Guide - Practice Questions

Study Guide - Flashcards