how might the headrest on a car prevent traumatic injury

HESI A2

Anatomy HESI A2

1. How might the headrest on a car prevent traumatic injury?

A. By limiting hyperflexion of the neck
B. By limiting hyperextension of the neck
C. By reducing vertebral compression
D. By preventing disc degeneration

Correct answer: B

Rationale: The headrest on a car is designed to prevent traumatic injury by limiting hyperextension of the neck during a rear-end collision. This helps reduce the risk of whiplash and other neck injuries that may occur when the head is forcefully thrown backward. Choice A is incorrect because hyperflexion is not the primary concern in rear-end collisions. Choice C is incorrect as the headrest does not directly reduce vertebral compression. Choice D is incorrect because the headrest is not directly involved in preventing disc degeneration.

2. What is the average normal body temperature in degrees Celsius?

A. 30°C
B. 32°C
C. 35°C
D. 37°C

Correct answer: D

Rationale: The average normal body temperature in degrees Celsius is 37°C. This temperature is considered the standard measurement for the human body under normal conditions. It is essential to know this baseline temperature for monitoring health and detecting abnormalities such as fever. Choice A, 30°C, is too low for the average normal body temperature. Choice B, 32°C, is also below the standard normal body temperature. Choice C, 35°C, is closer but still lower than the average normal body temperature of 37°C.

3. Which is an anterior muscle of the thigh?

A. Gluteus maximus
B. Quadriceps femoris
C. Biceps femoris
D. Adductor magnus

Correct answer: B

Rationale: The correct answer is B: Quadriceps femoris. The quadriceps femoris is an anterior muscle located on the front of the thigh. It is composed of four muscles: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. These muscles play a crucial role in extending the knee and are essential for activities like walking, running, and jumping. Choices A, C, and D are incorrect because they are not anterior muscles of the thigh. Gluteus maximus is a muscle located in the buttocks, biceps femoris is a muscle of the posterior thigh, and adductor magnus is a muscle of the medial thigh.

4. Which part of the brain is responsible for regulating breathing and heart rate?

A. Cerebrum
B. Medulla oblongata
C. Cerebellum
D. Hypothalamus

Correct answer: B

Rationale: The correct answer is the Medulla oblongata. This structure, located in the brainstem, plays a crucial role in regulating essential functions such as breathing, heart rate, and blood pressure. It serves as a control center for autonomic functions necessary for maintaining life. The Cerebrum (Choice A) is mainly responsible for higher brain functions such as thinking and voluntary movements, not for regulating basic physiological processes like breathing and heart rate. The Cerebellum (Choice C) is involved in coordination, balance, and muscle control, but not in regulating breathing and heart rate. The Hypothalamus (Choice D) plays a role in regulating body temperature, hunger, and thirst, but it is not primarily responsible for controlling breathing and heart rate.

5. What is the role of the alveoli in the lungs?

A. To filter blood
B. To exchange gases
C. To transport nutrients
D. To store oxygen

Correct answer: B

Rationale: The alveoli in the lungs are tiny air sacs responsible for the exchange of oxygen and carbon dioxide during breathing. Oxygen from inhaled air diffuses into the bloodstream through the alveoli, while carbon dioxide produced by cells is removed from the blood and exhaled out of the body through the alveoli. This gas exchange process is essential for the body to obtain oxygen and get rid of carbon dioxide, supporting cellular functions and maintaining overall health. Choices A, C, and D are incorrect because the alveoli do not filter blood, transport nutrients, or store oxygen. Their main function is gas exchange.