which organ is involved in the immune system

HESI A2

Quizlet HESI A2 Anatomy and Physiology

1. Which organ is involved in the immune system?

A. Heart
B. Bronchi
C. Appendix
D. Esophagus

Correct answer: C

Rationale: The correct answer is the Appendix. The appendix is now known to play a role in the immune system by housing beneficial bacteria that aid in maintaining gut health and supporting immune responses. This organ contributes to overall immune function. Choices A, B, and D are incorrect as the heart, bronchi, and esophagus are not primarily associated with the immune system.

2. What is the role of platelets in the blood?

A. To transport oxygen
B. To fight infections
C. To clot blood
D. To carry nutrients

Correct answer: C

Rationale: Platelets, also known as thrombocytes, play a crucial role in blood clotting. When there is an injury, platelets adhere to the site and release substances that form a clot, preventing excessive bleeding. This function is vital for maintaining hemostasis and preventing blood loss. Choice A is incorrect because red blood cells, not platelets, are responsible for transporting oxygen. Choice B is incorrect as white blood cells are primarily responsible for fighting infections. Choice D is incorrect as nutrients are mainly transported by plasma and red blood cells, not platelets.

3. How do the intercostal muscles between the ribs assist with respiration?

A. By protecting the delicate bronchioles and alveoli
B. By signaling a decrease in intra-alveolar pressure
C. By enlarging and reducing the space in the thorax
D. By maintaining a medial separation between pleurae

Correct answer: C

Rationale: The intercostal muscles located between the ribs play a crucial role in respiration by aiding in the enlargement and reduction of the space in the thorax. During inspiration, these muscles contract, lifting the rib cage, which increases the volume of the thoracic cavity and allows the lungs to expand and fill with air. This process directly relates to the expansion of the thorax rather than protecting bronchioles and alveoli (Choice A), signaling intra-alveolar pressure changes (Choice B), or maintaining the separation between pleurae (Choice D). Therefore, the correct answer is C.

4. Which is another name for thiamine?

A. Vitamin B1
B. Vitamin B2
C. Vitamin B6
D. Vitamin D

Correct answer: A

Rationale: Thiamine is another name for Vitamin B1. It is an essential vitamin that plays a crucial role in energy metabolism and is important for the proper functioning of the nervous system. Vitamin B2 is riboflavin, not thiamine. Vitamin B6 is pyridoxine, not thiamine. Vitamin D is a different vitamin responsible for calcium absorption and bone health, not thiamine. Therefore, the correct answer is Vitamin B1.

5. What is the primary role of the small intestine in nutrient absorption?

A. To break down food
B. To absorb nutrients
C. To secrete digestive enzymes
D. To store glucose

Correct answer: B

Rationale: The correct answer is B: 'To absorb nutrients.' The small intestine is the primary site for nutrient absorption in the digestive system. It plays a crucial role in absorbing nutrients from digested food into the bloodstream, facilitating the delivery of essential nutrients to the body for various functions and processes. Choices A, C, and D are incorrect because while the small intestine does contribute to the breakdown of food and does secrete digestive enzymes, its primary function is to absorb nutrients, not to store glucose.