Nursing Elites

1. What is the structure and function of elastic arteries?

• A. They are the smallest arteries and constrict and dilate frequently.
• B. They are medium-sized arteries that distribute blood to various organs.
• C. They are the largest arteries and stretch and recoil to accommodate blood pressure changes.
• D. They are thin-walled arteries that supply blood to the capillaries.

Correct answer: C

Rationale: The corrected answer is C. Elastic arteries, like the aorta, are the largest arteries in the body. They possess elastic fibers in their walls, allowing them to stretch and recoil in response to the pulsatile nature of blood flow from the heart. This elasticity helps to maintain blood pressure by absorbing the pressure waves generated by the heart's contractions and ensuring continuous blood flow to the organs. Choices A, B, and D are incorrect because elastic arteries are not the smallest arteries, do not constrict and dilate frequently, are not medium-sized arteries for distributing blood to various organs, and are not thin-walled arteries supplying blood to capillaries. Elastic arteries have a specific structure and function related to their ability to accommodate blood pressure changes due to their elastic properties, which is essential for the cardiovascular system's proper functioning.

2. What is the process by which lighter nuclei fuse to form heavier nuclei, releasing a large amount of energy?

• A. Fission
• B. Fusion
• C. Radioactivity
• D. Chain reaction

Correct answer: B

Rationale: Fusion is the process by which lighter nuclei combine to form heavier nuclei, releasing a large amount of energy in the process. This process is the source of energy in stars, including our Sun. Fission, the process of splitting heavier nuclei into lighter nuclei, is not correct. Radioactivity involves the emission of particles or radiation from the nucleus of an unstable atom, which is different from fusion. A chain reaction is a self-sustaining reaction where the products of one reaction cause further reactions, which is unrelated to fusion.

3. Which hormone is produced by the thyroid gland?

• A. Insulin
• B. Thyroxine
• C. Adrenaline
• D. Cortisol

Correct answer: B

Rationale: The correct answer is B: Thyroxine. The thyroid gland produces thyroxine, a hormone essential for regulating metabolism. Insulin is produced by the pancreas to regulate blood sugar levels. Adrenaline is produced by the adrenal glands to prepare the body for the 'fight or flight' response. Cortisol is produced by the adrenal cortex in response to stress, not by the thyroid gland.

4. What is the main component of sweat?

• A. Urea
• B. Glucose
• C. Water
• D. Electrolytes

Correct answer: C

Rationale: - Sweat is primarily composed of water, making up the majority of its content. Water helps regulate body temperature by evaporating from the skin's surface, which cools the body down. - While sweat does contain small amounts of other substances like urea, glucose, and electrolytes, water is the main component that is secreted by sweat glands to help regulate body temperature during physical activity or in response to heat.

5. If a biochemist isolates a large amount of pyruvate, which part of the cell is he working with?

• A. Chloroplasts
• B. Cytoplasm
• C. Mitochondria
• D. Nucleus

Correct answer: B

Rationale: The correct answer is B: Cytoplasm. Pyruvate is a product of glycolysis, a metabolic pathway that takes place in the cytoplasm of the cell. Therefore, a biochemist isolating a large amount of pyruvate would be working with the cytoplasm of the cell. Choice A, Chloroplasts, is incorrect because pyruvate is not produced in chloroplasts, which are responsible for photosynthesis. Choice C, Mitochondria, is incorrect as pyruvate is produced in the cytoplasm before entering the mitochondria for further metabolism. Choice D, Nucleus, is incorrect as the nucleus is not involved in the production or isolation of pyruvate, which is a metabolic intermediate.

Similar Questions