which gland is often referred to as the master gland

HESI A2

HESI A2 Practice Test Anatomy and Physiology

1. Which gland is often referred to as the 'master gland'?

A. Thyroid gland
B. Pituitary gland
C. Adrenal gland
D. Pineal gland

Correct answer: B

Rationale: The pituitary gland is often referred to as the 'master gland' because it controls the release of hormones from other endocrine glands in the body. It secretes a variety of hormones that regulate various bodily functions and play a crucial role in maintaining homeostasis. The thyroid gland (Choice A) plays a role in regulating metabolism, the adrenal gland (Choice C) secretes hormones involved in stress response, and the pineal gland (Choice D) produces melatonin to regulate sleep-wake cycles, but they are not known as the 'master gland' due to their functions.

2. What is the meaning of endocytosis?

A. The cell engulfs solid particles.
B. The cell engulfs liquid material.
C. The cell expels solid particles.
D. The cell releases liquid material.

Correct answer: A

Rationale: Endocytosis is a cellular process where the cell engulfs and internalizes solid particles by forming vesicles. It is a mechanism used for nutrient uptake, cell signaling, and maintaining cellular homeostasis. Options B, C, and D describe processes that are opposite to endocytosis. Choice B is incorrect because it describes pinocytosis, which is the process of engulfing liquid material. Choice C is incorrect as it describes exocytosis, the process of expelling material from the cell. Choice D is incorrect as it describes the process of releasing liquid material from the cell. Therefore, the correct answer is A.

3. What is the main function of the digestive system?

A. To break down food and absorb nutrients
B. To regulate body temperature
C. To transport nutrients
D. To produce hormones

Correct answer: A

Rationale: The main function of the digestive system is to break down food into nutrients through the process of digestion. Once the food is broken down, the nutrients are absorbed into the bloodstream and utilized by the body for various functions. Choice B, regulating body temperature, is incorrect as it is the function of the body's thermoregulatory system, not the digestive system. Choice C, transporting nutrients, is incorrect as the digestive system primarily focuses on breaking down and absorbing nutrients rather than transporting them. Choice D, producing hormones, is also incorrect as hormone production is mainly carried out by endocrine glands and not the digestive system.

4. Which of the following HDL cholesterol levels might warrant regular testing?

A. 70 or higher
B. 60
C. 50
D. 40

Correct answer: A

Rationale: An HDL cholesterol level of 70 or higher is considered high and beneficial for heart health. Individuals with high HDL levels are usually at lower risk of heart disease. Therefore, a level of 70 or above would warrant regular testing to monitor and maintain heart health. Choices B, C, and D are lower levels of HDL cholesterol, which are not typically considered high enough to warrant regular testing as they may not provide the same level of heart health benefits.

5. Why might certain young people be underweight?

A. They are growing in height faster than they are gaining weight.
B. They eat little protein and too much fat and sugar.
C. They eat several meals a day and fail to exercise enough.
D. They seldom eat a meal that contains foods from all food groups.

Correct answer: A

Rationale: Certain young people might be underweight because they are growing in height faster than they are gaining weight. During periods of rapid growth, the body's energy requirements are primarily directed towards height growth rather than weight gain, resulting in some individuals being underweight despite consuming sufficient calories. Choice B is incorrect because the question focuses on reasons related to growth rather than diet composition. Choice C is incorrect as it suggests overeating rather than the specific growth-related issue of height surpassing weight gain. Choice D is incorrect as it addresses nutritional variety rather than the growth dynamics affecting weight.