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 main function of the endocrine system?

A. To fight infections
B. To regulate body functions through hormones
C. To produce red blood cells
D. To transport oxygen

Correct answer: B

Rationale: The main function of the endocrine system is to regulate various body functions by releasing hormones, which act as chemical messengers. These hormones help maintain homeostasis, regulate metabolism, growth, development, and other essential functions in the body. Option A is incorrect as fighting infections is primarily the role of the immune system, not the endocrine system. Option C is incorrect as the production of red blood cells mainly occurs in the bone marrow. Option D is incorrect as the transportation of oxygen is primarily carried out by the respiratory and circulatory systems. Therefore, option B is the correct answer as it accurately describes the primary role of the endocrine system.

3. Which of the following is known as the production of red blood cells?

A. Thrombopoiesis
B. Erythropoiesis
C. Hematopoiesis
D. Phagocytosis

Correct answer: B

Rationale: Erythropoiesis specifically refers to the process of producing red blood cells (erythrocytes) in the bone marrow. Hematopoiesis is the broader term that encompasses the production of all types of blood cells, including red blood cells, white blood cells, and platelets. Phagocytosis is the process by which cells engulf and digest particles, while thrombopoiesis is the production of platelets. Therefore, the correct answer is B as it directly relates to the production of red blood cells.

4. What is the function of the skin in protecting the body?

A. To produce vitamin D
B. To protect against pathogens
C. To store nutrients
D. To regulate body temperature

Correct answer: B

Rationale: The skin serves several crucial functions in protecting the body. One of its primary roles is to act as a physical barrier against pathogens, preventing harmful microorganisms from entering the body. Choice A, 'To produce vitamin D,' is incorrect because while the skin is involved in vitamin D synthesis upon exposure to sunlight, its primary protective role is against pathogens. Choice C, 'To store nutrients,' is incorrect as the skin is not a primary organ for nutrient storage. Choice D, 'To regulate body temperature,' is a function of the skin, but the primary role in protecting the body is to act as a barrier against pathogens.

5. Which structure in the eye is responsible for focusing light on the retina?

A. Cornea
B. Lens
C. Retina
D. Pupil

Correct answer: B

Rationale: The lens of the eye is responsible for focusing light onto the retina. It plays a crucial role in bending light rays to ensure that they converge on the retina, enabling clear vision. The cornea helps in focusing light, but the final adjustment and fine-tuning occur through the lens. The retina receives the focused light and converts it into neural signals for the brain to interpret. The pupil, on the other hand, controls the amount of light entering the eye by dilating or constricting.