which organ system is primarily responsible for regulating muscle growth

HESI A2

Anatomy HESI A2

1. Which organ system is primarily responsible for regulating muscle growth?

A. The skeletal system
B. The endocrine system
C. The nervous system
D. The reproductive system

Correct answer: B

Rationale: The endocrine system is primarily responsible for regulating muscle growth through the production and release of hormones such as growth hormone, testosterone, and insulin-like growth factors. These hormones play crucial roles in stimulating muscle protein synthesis, increasing muscle mass, and promoting overall muscle growth and repair. The skeletal system provides structural support for muscles but does not directly regulate muscle growth. The nervous system controls muscle contractions and movements but is not primarily responsible for muscle growth. The reproductive system plays a role in fertility and secondary sexual characteristics but does not have a direct role in regulating muscle growth.

2. Which of the following statements best describes endocrine glands?

A. They secrete chemicals into the blood
B. They secrete enzymes into ducts
C. They produce sweat
D. They produce saliva

Correct answer: A

Rationale: Endocrine glands are ductless glands that release hormones directly into the bloodstream. These hormones are then carried to target organs and tissues throughout the body, where they regulate various physiological functions. The statement 'They secrete chemicals into the blood' accurately describes the function of endocrine glands. Choices B, C, and D are incorrect because endocrine glands do not secrete enzymes into ducts, produce sweat, or produce saliva. These functions are typically associated with exocrine glands, sweat glands, and salivary glands, respectively.

3. Which hormone is released by the pancreas to lower blood glucose levels?

A. Insulin
B. Glucagon
C. Cortisol
D. Somatostatin

Correct answer: A

Rationale: Insulin is the hormone released by the pancreas to lower blood glucose levels. Insulin facilitates the uptake of glucose into cells, helping to decrease blood glucose levels and store excess glucose for energy or future use. Glucagon, on the other hand, raises blood glucose levels by promoting the breakdown of glycogen into glucose. Cortisol and somatostatin do not directly regulate blood glucose levels in the same manner as insulin and glucagon.

4. Which vitamin is essential for the synthesis of collagen?

A. Vitamin C
B. Vitamin D
C. Vitamin B12
D. Vitamin K

Correct answer: A

Rationale: The correct answer is Vitamin C. Vitamin C is essential for the synthesis of collagen, a protein crucial for maintaining the structure and integrity of skin, blood vessels, and bones. It plays a key role in the hydroxylation of proline and lysine residues in collagen synthesis, which is necessary for the stability and strength of collagen fibers. Choice B: Vitamin D is essential for bone health and calcium absorption but is not directly involved in collagen synthesis. Choice C: Vitamin B12 is important for red blood cell formation and neurological function but is not directly related to collagen synthesis. Choice D: Vitamin K is necessary for blood clotting and bone metabolism but does not play a direct role in collagen synthesis.

5. Which of the following structures is part of both the male reproductive system and the urinary system?

A. Bladder
B. Urethra
C. Prostate
D. Seminal Vesicle

Correct answer: B

Rationale: The urethra is the correct answer as it is a structure shared by both the male reproductive and urinary systems. It functions as a conduit for both urine from the bladder and semen from the reproductive system, making it a crucial component of both systems. The bladder (Choice A) is solely part of the urinary system, storing urine. The prostate (Choice C) and seminal vesicle (Choice D) are structures specific to the male reproductive system, involved in producing and secreting components of semen.