1. The stomach produces a strong acid to help break down food. What is the name of this acid?

A. Hydrochloric acid
B. Lactic acid
C. Bile
D. Fatty acid

Correct answer: A

Rationale: The correct answer is A: Hydrochloric acid. The stomach produces hydrochloric acid to help break down food by lowering the pH level in the stomach, creating an acidic environment that aids in the digestion of proteins and other nutrients. Lactic acid is produced in muscles during exercise and is not related to stomach digestion. Bile is produced by the liver and helps in the digestion and absorption of fats in the small intestine. Fatty acids are a type of molecule that is a component of fats, not the acid produced by the stomach for digestion.

2. In the cardiovascular system, what is the primary function of red blood cells?

A. To transport oxygen throughout the body.
B. To fight infection and disease.
C. To help regulate blood clotting.
D. To remove waste products from the body.

Correct answer: A

Rationale: The correct answer is A: 'To transport oxygen throughout the body.' Red blood cells contain hemoglobin, a protein that binds to oxygen in the lungs and carries it to tissues throughout the body. This process is essential for cellular respiration, where oxygen is used to produce energy. Red blood cells do not fight infection (B), regulate blood clotting (C), or remove waste products (D); those functions are carried out by other components of the immune and circulatory systems.

3. 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.

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. Which hormone, produced by the adrenal glands, plays a crucial role in the body's response to stress, including the regulation of salt and water balance?

A. Aldosterone
B. Epinephrine
C. Cortisol
D. Insulin

Correct answer: A

Rationale: The correct answer is A: Aldosterone. Aldosterone is a hormone produced by the adrenal glands that plays a crucial role in the body's response to stress by regulating salt and water balance. It acts on the kidneys to increase the reabsorption of sodium and water, helping to maintain blood pressure and electrolyte balance during times of stress. Epinephrine and cortisol are also stress hormones produced by the adrenal glands, but they have different functions. Epinephrine is involved in the fight-or-flight response, while cortisol helps regulate metabolism and immune function. Insulin, produced by the pancreas, is involved in glucose metabolism and not directly related to the body's stress response. Therefore, aldosterone is the most appropriate hormone in this context.