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. A person who has damage to their ulnar nerve will have decreased sensation in which part of the body?

A. Hand
B. Arm
C. Leg
D. Foot

Correct answer: A

Rationale: Corrected Rationale: Damage to the ulnar nerve typically results in decreased sensation in the hand, particularly affecting the little finger and half of the ring finger. The ulnar nerve innervates the hand and is responsible for providing sensation to these areas. This nerve does not extend to the leg or foot, so choices C and D are incorrect. While the ulnar nerve travels through the arm, its primary sensory impact is felt in the hand, making choice B less specific and therefore not the best answer.

3. What is the role of the spleen in the lymphatic system?

A. To filter blood and remove old red blood cells
B. To produce lymphocytes
C. To store vitamins
D. To regulate body temperature

Correct answer: A

Rationale: The spleen plays a crucial role in the lymphatic system by filtering blood, specifically removing old or damaged red blood cells. Additionally, the spleen produces lymphocytes, a type of white blood cell that plays a key role in the immune response by helping to fight off infections. Therefore, the correct answer is A, as the spleen is primarily involved in blood filtration and the production of lymphocytes rather than storing vitamins or regulating body temperature.

4. Which organ system is primarily responsible for maintaining temperature control?

A. The skeletal system
B. The digestive system
C. The nervous system
D. The integumentary system

Correct answer: D

Rationale: The integumentary system, which includes the skin, hair, and nails, is primarily responsible for maintaining temperature control in the body. The skin helps regulate body temperature through processes like sweating to cool down and shivering to generate heat. Additionally, blood vessels in the skin can dilate or constrict to control the amount of heat lost or retained by the body. This system plays a crucial role in maintaining homeostasis and keeping the body at a stable temperature. The skeletal system (Choice A) provides structural support and protection to the body but is not directly involved in temperature regulation. The digestive system (Choice B) is responsible for breaking down food and absorbing nutrients, not for regulating body temperature. The nervous system (Choice C) controls body functions through electrical impulses but is not the primary system responsible for temperature control.

5. Which parts of the heart are separated by the mitral valve?

A. Left atrium and right atrium
B. Right atrium and right ventricle
C. Left ventricle and right ventricle
D. Left atrium and left ventricle

Correct answer: D

Rationale: The mitral valve, also known as the bicuspid valve, separates the left atrium and the left ventricle of the heart. Its primary function is to prevent the backflow of blood from the left ventricle to the left atrium during the heart's contraction. Therefore, option D, 'Left atrium and left ventricle,' is the correct answer. Choices A, B, and C are incorrect because they do not represent the parts separated by the mitral valve.