which cut is considered a cross section

HESI A2

HESI A2 Anatomy and Physiology Practice Test

1. Which cut is considered a cross section?

A. A sagittal or frontal section
B. A cut along the coronal plane
C. A cut along the median plane
D. A cut through the transverse plane

Correct answer: D

Rationale: The correct answer is D: A cut through the transverse plane. A transverse plane cut, also known as a cross-section, divides the body or an organ into superior and inferior portions. This type of cut is perpendicular to the long axis of the body and is commonly used in medical imaging to display internal structures and organs in a horizontal view. Choices A, B, and C are incorrect because a sagittal or frontal section (A) divides the body into left and right portions, a cut along the coronal plane (B) separates the body into anterior and posterior parts, and a cut along the median plane (C) divides the body into equal left and right halves.

2. A cell from heart muscle would more than likely contain an unusually high proportion of which of the following?

A. lysosomes
B. mitochondria
C. mRNA
D. ribosomes

Correct answer: B

Rationale: A cell from heart muscle would more than likely contain an unusually high proportion of mitochondria because the heart muscle requires a significant amount of energy to function properly. Mitochondria are the powerhouse of the cell and are responsible for producing energy in the form of ATP through cellular respiration. Therefore, to meet the high energy demands of the heart muscle, it would need a higher concentration of mitochondria compared to other cell types. Choices A, C, and D are incorrect because while lysosomes, mRNA, and ribosomes are essential components of a cell, they do not play as direct a role in meeting the high energy demands of heart muscle as mitochondria do.

3. Which structure in the ear is responsible for balance?

A. Cochlea
B. Semicircular canals
C. Ossicles
D. Eustachian tube

Correct answer: B

Rationale: The semicircular canals in the inner ear are responsible for maintaining balance by detecting changes in head position and movement. These structures contain fluid and hair cells that send signals to the brain regarding the body's orientation in space, helping us stay balanced and navigate our surroundings. The cochlea is responsible for hearing, the ossicles are involved in sound transmission, and the Eustachian tube helps equalize pressure in the middle ear, but they are not directly related to balance.

4. What is the freezing point of water in degrees Celsius?

A. 0°C
B. 100°C
C. 50°C
D. 25°C

Correct answer: A

Rationale: The correct answer is 0°C. The freezing point of water is 0°C under standard conditions. Water freezes at 0°C and boils at 100°C. Choices B, C, and D are incorrect because they do not represent the freezing point of water. 100°C is the boiling point of water, 50°C and 25°C are not related to the freezing point of water.

5. Express 2/5 as a decimal.

A. 0.2
B. 0.25
C. 0.4
D. 2.5

Correct answer: C

Rationale: To express 2/5 as a decimal, you divide the numerator (2) by the denominator (5). 2 ÷ 5 = 0.4. Choice A (0.2) is the decimal equivalent of 1/5, not 2/5. Choice B (0.25) is the decimal equivalent of 1/4, not 2/5. Choice D (2.5) is not the correct decimal equivalent of 2/5 as it is greater than 1.