1. What is the name of the bone marrow cavity in the long bones where red blood cells are produced?

A. Periosteum
B. Diaphysis
C. Medullary cavity
D. Epiphysis

Correct answer: B

Rationale: The correct answer is B: Diaphysis. The diaphysis is the shaft of a long bone where the medullary cavity is located. The medullary cavity is the central cavity of the diaphysis where red bone marrow is found and is responsible for producing red blood cells, white blood cells, and platelets. The periosteum is a dense membrane covering the outer surface of bones, not where red blood cells are produced. The epiphysis refers to the ends of long bones, while the medullary cavity is found in the diaphysis. Therefore, the correct choice is the diaphysis where the medullary cavity is located for red blood cell production.

2. Bradycardia refers to a heart rate that is:

A. Normal (60-100 bpm)
B. Slightly elevated (100-120 bpm)
C. Significantly elevated (>120 bpm)
D. Abnormally slow (<60 bpm)

Correct answer: D

Rationale: The correct answer is D. Bradycardia refers to an abnormally slow heart rate, typically defined as being less than 60 beats per minute (bpm). A heart rate of 60-100 bpm is considered normal, not bradycardia. Choices B and C incorrectly describe elevated heart rates, which are not characteristic of bradycardia. Therefore, option D is the most accurate description of bradycardia as it signifies a heart rate that is slower than normal.

3. Passive transport does not require energy input from the cell. Which of the following is an example of passive transport?

A. Active transport of ions across a membrane
B. Diffusion of small molecules across a concentration gradient
C. Movement of large molecules using vesicles
D. Endocytosis of particles into the cell

Correct answer: D

Rationale: Passive transport refers to the movement of molecules across a cell membrane without the need for energy input. Endocytosis is an example of passive transport because it involves the cell engulfing particles or molecules from the external environment into vesicles without the direct expenditure of energy. On the other hand, options A, B, and C involve active processes that require energy. Active transport, such as the movement of ions against their concentration gradient, requires energy in the form of ATP. Diffusion of small molecules across a concentration gradient also does not require energy input, but it is a passive process, not active transport. Movement of large molecules using vesicles is a form of active transport called vesicular transport. Therefore, the correct answer is D, endocytosis of particles into the cell, as it exemplifies passive transport without the need for energy consumption by the cell.

4. Discern the INCORRECT function of the liver.

A. Bile production, aiding digestion.
B. Blood protein synthesis, such as albumin.
C. Glucose storage for energy regulation.
D. Filtration of waste products from the blood.

Correct answer: D

Rationale: Rationale: A) Correct - The liver produces bile, which aids in the digestion and absorption of fats in the small intestine. B) Correct - The liver is responsible for synthesizing blood proteins, including albumin, which helps maintain osmotic pressure in the blood. C) Correct - The liver stores glucose in the form of glycogen and helps regulate blood sugar levels by releasing glucose when needed. D) Incorrect - The liver does not filter waste products from the blood. Instead, the kidneys are responsible for filtering waste products from the blood and excreting them in the form of urine.

5. Negative feedback mechanisms are crucial in the endocrine system to:

A. Increase hormone production continuously
B. Maintain hormone levels within a specific range
C. Cause a constant release of hormones
D. Disrupt communication between glands

Correct answer: B

Rationale: The correct answer is B: 'Maintain hormone levels within a specific range.' Negative feedback mechanisms in the endocrine system are essential for regulating hormone levels. These mechanisms work to counteract any deviations from the set point, ensuring that hormone levels remain balanced and within the optimal range for proper physiological function. Continuous hormone production (A) or constant release of hormones (C) would lead to imbalances and potential harm to the body. Disrupting communication between glands (D) would hinder the coordination necessary for maintaining homeostasis. Therefore, option B is the best choice as it highlights the critical role of negative feedback in keeping hormone levels stable and regulated.

6. Which of the following is NOT a function of the endocrine system?

A. Regulating growth and development
B. Maintaining blood sugar levels
C. Controlling mood and emotions
D. Facilitating digestion through muscle contractions

Correct answer: D

Rationale: The endocrine system is responsible for producing hormones that regulate various bodily functions. Option D, facilitating digestion through muscle contractions, is actually a function of the muscular and digestive systems, not the endocrine system. The endocrine system primarily regulates growth and development, maintains blood sugar levels through hormones like insulin and glucagon, and also plays a role in controlling mood and emotions through hormones such as serotonin and cortisol. Therefore, option D is correct as it is not a function directly associated with the endocrine system.