which hormone stimulates milk production in the breasts during lactation

HESI A2

Anatomy HESI A2

1. Which hormone stimulates milk production in the breasts during lactation?

A. norepinephrine
B. antidiuretic hormone
C. prolactin
D. oxytocin

Correct answer: C

Rationale: During lactation, the hormone responsible for stimulating milk production in the breasts is 'prolactin.' Prolactin plays a crucial role in initiating and maintaining lactation by promoting the development of alveoli in the mammary glands and stimulating milk synthesis. While oxytocin is involved in the ejection of milk from the breasts, it is prolactin that primarily governs milk production. Norepinephrine is not directly involved in milk production, and antidiuretic hormone primarily regulates water balance and blood pressure, not milk production.

2. How do the digestive system and urinary system work together?

A. The digestive system controls the function of the ureter.
B. The urinary system removes toxins from the products of digestion.
C. The digestive system manufactures hormones that influence urination.
D. The urinary system eliminates some waste products of digestion.

Correct answer: D

Rationale: The correct answer is D because the urinary system eliminates some waste products of digestion. After digestion in the digestive system, nutrients are absorbed into the bloodstream, and waste products are transported to the kidneys via the urinary system to be excreted as urine. This process helps eliminate waste products generated during digestion, illustrating the coordination between the digestive and urinary systems. Choices A, B, and C are incorrect. Choice A is incorrect as the ureter is part of the urinary system, not controlled by the digestive system. Choice B is incorrect as the urinary system primarily removes metabolic waste, not toxins from digestion. Choice C is incorrect because the digestive system mainly aids in digestion and nutrient absorption, not hormone production affecting urination.

3. Enlargement of the thyroid, commonly known as a goiter, might be expected to affect ___________.

A. swallowing
B. insulin levels
C. sleep
D. digestion

Correct answer: A

Rationale: Enlargement of the thyroid, known as a goiter, can compress the nearby structures in the neck, including the esophagus. This compression can lead to symptoms such as difficulty swallowing (dysphagia) or a sensation of pressure in the throat. Therefore, an enlarged thyroid gland is expected to affect swallowing. Choices B, C, and D are incorrect because a goiter primarily affects structures in the neck due to its physical enlargement, rather than directly impacting insulin levels, sleep, or digestion.

4. Which part of the brain controls voluntary movement?

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

Correct answer: B

Rationale: The cerebrum, specifically the motor cortex located within it, is responsible for controlling voluntary movements such as walking, writing, and speaking. This region of the brain plays a crucial role in coordinating and executing voluntary muscle actions, making it the correct answer in this context. The cerebellum (Choice A) primarily coordinates balance, posture, and coordination of voluntary movements but does not control voluntary movement itself. The brainstem (Choice C) is responsible for basic life functions like breathing and heart rate, not voluntary movements. The medulla oblongata (Choice D) controls vital functions like blood pressure and breathing, not voluntary movement.

5. Beriberi is a disease caused by a lack of ___________.

A. thiamine
B. vitamin C
C. niacin
D. protein

Correct answer: A

Rationale: Beriberi is a disease caused by a deficiency of thiamine, also known as vitamin B1. Thiamine is essential for the proper functioning of the nervous system and energy metabolism in the body. Without enough thiamine, individuals may develop symptoms such as weakness, fatigue, nerve damage, and heart problems, which are characteristic of beriberi. Vitamin C (choice B), niacin (choice C), and protein (choice D) deficiencies can cause other health issues but are not directly related to beriberi.