Which of the following is NOT an example of a homeostatic mechanism?
- A. Shivering when the body temperature falls.
- B. Increasing heart rate when blood pressure is low.
- C. Weight gain when consuming excess calories.
- D. Secreting insulin to decrease blood sugar concentration.
Correct Answer: C
Rationale: Weight gain when consuming excess calories is not an example of a homeostatic mechanism. Homeostasis refers to the body's ability to maintain a stable internal environment despite external changes. The other options listed (A, B, and D) involve physiological responses aimed at restoring balance or stability within the body (e.g., regulating body temperature, blood pressure, and blood sugar levels). Shivering, increasing heart rate, and secreting insulin are mechanisms to counteract specific imbalances and maintain internal equilibrium. In contrast, weight gain due to excess calorie intake does not represent a specific regulatory mechanism but rather an outcome of energy imbalance. The body stores excess energy as fat rather than actively regulating a physiological parameter to restore balance.
You may also like to solve these questions
Which of the following functions is NOT performed by the integumentary system, the skin?
- A. Protect internal tissues from injury
- B. Waterproof the body
- C. Help regulate body temperature
- D. Return fluid to the blood vessels
Correct Answer: D
Rationale: The integumentary system, which includes the skin, performs various functions like protecting internal tissues from injury, waterproofing the body, and helping regulate body temperature. The function of returning fluid to the blood vessels is primarily associated with the lymphatic system, not the integumentary system. The skin contributes to fluid balance by regulating sweating and preventing excessive water loss, but it does not directly return fluid to the blood vessels, making this the correct answer. Choices A, B, and C are functions directly related to the integumentary system and are essential for maintaining the body's overall health and well-being.
What is the name of the outermost layer of the skin?
- A. Dermis
- B. Epidermis
- C. Subcutaneous tissue
- D. Hypodermis
Correct Answer: B
Rationale: The correct answer is B: Epidermis. The epidermis is the outermost layer of the skin, providing a protective barrier against external factors. The dermis is situated beneath the epidermis and contains structures like blood vessels and hair follicles. Subcutaneous tissue, also known as the hypodermis, lies below the dermis and consists mainly of fat tissue, serving functions such as insulation and energy storage. Therefore, choices A, C, and D are incorrect as they do not represent the outermost layer of the skin.
Where would a nonpregnant patient with normal anatomy most commonly have pain in acute appendicitis?
- A. Right upper quadrant.
- B. Left upper quadrant.
- C. Right lower quadrant.
- D. Left lower quadrant.
Correct Answer: C
Rationale: In acute appendicitis, nonpregnant patients with normal anatomy commonly experience pain in the right lower quadrant of the abdomen. The pain usually starts around the umbilicus or epigastric area and then migrates to the right lower quadrant as inflammation progresses in the appendix. This classic migration of pain is known as McBurney's point tenderness and is a key clinical feature in diagnosing appendicitis.
What is the process called in which a substance changes from a gas to a liquid?
- A. Condensation.
- B. Evaporation.
- C. Sublimation.
- D. Vaporization.
Correct Answer: A
Rationale: Condensation is indeed the correct answer. It is the process by which a substance changes from a gas to a liquid. This occurs when the temperature of a gas decreases enough for its particles to lose energy and come together to form a liquid. On the other hand, evaporation is the process of a liquid changing to a gas. Sublimation is the direct transition of a substance from a solid to a gas without passing through the liquid phase. Vaporization, on the other hand, is the general term for the process of a liquid changing to a gas, which includes both evaporation and boiling.
What is the primary function of antibodies?
- A. Production of white blood cells
- B. Initiation of gluconeogenesis
- C. Promotion of intracellular storage of lipids
- D. Facilitate the breakdown of antigens
Correct Answer: D
Rationale: The correct answer is D: Facilitate the breakdown of antigens. Antibodies are protein molecules produced by the immune system in response to the presence of foreign substances, known as antigens, in the body. Antibodies bind to specific antigens and mark them for destruction by other immune cells, thereby helping the body to defend against infections and other threats. Choices A, B, and C are incorrect because antibodies do not have a direct role in the production of white blood cells, initiation of gluconeogenesis, or promotion of intracellular storage of lipids. The primary function of antibodies is to target and facilitate the destruction of antigens in the body.