which organ is responsible for filtering and cleaning the blood

HESI A2

HESI A2 Anatomy and Physiology Practice Test 2023

1. Which organ is responsible for filtering and cleaning the blood?

A. Lungs
B. Heart
C. Kidneys
D. Liver

Correct answer: C

Rationale: The correct answer is C: Kidneys. The kidneys are the organs responsible for filtering and cleaning the blood. They remove waste products, regulate electrolyte levels, and help maintain fluid balance in the body through the production of urine. The other choices are incorrect because: A) Lungs are primarily responsible for gas exchange, not blood filtration. B) The heart is responsible for pumping blood, not filtering it. D) The liver plays a role in detoxification and metabolism, but it is not primarily responsible for filtering and cleaning the blood.

2. Which might be a good title for this passage?

A. “Everyone Should Run Barefoot”
B. “How to Prevent Running Injuries”
C. “Modern Road Surfaces Versus Barefoot Running”
D. “The Debate over Barefoot Running”

Correct answer: D

Rationale: The title "The Debate over Barefoot Running" encapsulates the central theme of the passage, which explores both the advantages and disadvantages of barefoot running. It effectively summarizes the discussions around differing opinions and the lack of consensus on this topic. Other titles do not accurately reflect the primary focus of the essay, making D the most suitable choice.

3. 30 1/2 - 13 3/4 = ?

A. 16 3/4
B. 17
C. 15 1/4
D. 15

Correct answer: A

Rationale: To solve the expression 30 1/2 - 13 3/4, first convert the mixed numbers to improper fractions. 30 1/2 is equivalent to 61/2 and 13 3/4 is equivalent to 55/4. Subtracting 55/4 from 61/2 gives 16 3/4, which is the correct answer. Choice B (17) is incorrect as the correct answer is a mixed number, not a whole number. Choice C (15 1/4) is incorrect as it doesn't result from subtracting the given fractions. Choice D (15) is incorrect; the correct answer is greater than 15.

4. Which type of muscle is found in the walls of hollow organs?

A. Skeletal muscle
B. Cardiac muscle
C. Smooth muscle
D. Striated muscle

Correct answer: C

Rationale: Smooth muscle tissue is found in the walls of hollow organs, such as the intestines, blood vessels, and bladder. It contracts involuntarily, allowing for movements like peristalsis in the intestines and regulation of blood flow in blood vessels. Skeletal muscle (Choice A) is attached to bones and helps in voluntary movements. Cardiac muscle (Choice B) is found in the heart and contracts involuntarily to pump blood. Striated muscle (Choice D) refers to both skeletal and cardiac muscles, which have a striped appearance due to the organization of their filaments. However, smooth muscle (Choice C) is specifically the type found in hollow organs.

5. According to Bernoulli's principle, when the flow velocity (v) of an incompressible fluid increases in a constricted pipe, the pressure (P) will:

A. Depend on the specific fluid type
B. Decrease
C. Remain constant
D. Increase

Correct answer: B

Rationale: Bernoulli's principle states that in a constricted pipe with increasing flow velocity of an incompressible fluid, the pressure decreases. This is due to the conservation of energy, where the total energy of the fluid (sum of kinetic energy, potential energy, and pressure energy) remains constant along the flow path. As the fluid velocity increases, its kinetic energy increases at the expense of pressure energy, causing a decrease in pressure. Therefore, the correct answer is B. Choices A, C, and D are incorrect. The pressure changes in the system are primarily driven by the fluid velocity and the conservation of energy principle, not by the specific fluid type, which is a constant. The pressure is not constant but decreases with increasing flow velocity due to the energy transformation occurring in the system. Lastly, the pressure does not increase; it decreases as the fluid velocity rises.