Nursing Elites

1. Which term describes the ability of a muscle to return to its original length and shape after being stretched or contracted?

• A. Contractility
• B. Elasticity
• C. Extensibility
• D. Excitability

Correct answer: B

Rationale: Elasticity is the correct term that describes the ability of a muscle to return to its original length and shape after being stretched or contracted. Contractility refers to the ability of a muscle to contract or shorten. Extensibility is the ability of a muscle to be stretched. Excitability is the ability of a muscle to receive and respond to stimuli. Therefore, the correct answer is 'Elasticity' as it specifically relates to the muscle's ability to regain its original form.

2. Which hormone is crucial for stimulating sperm production in males?

• A. Estrogen
• B. Progesterone
• C. Testosterone
• D. Insulin

Correct answer: C

Rationale: Testosterone is the hormone crucial for stimulating sperm production in males. It is primarily produced in the testes and plays a significant role in the development of male reproductive tissues, including the testes and prostate, as well as promoting secondary sexual characteristics such as facial hair growth and deepening of the voice. Estrogen and progesterone are female sex hormones responsible for regulating the menstrual cycle and other female reproductive functions. Insulin, on the other hand, is involved in regulating blood sugar levels and glucose metabolism, not directly related to sperm production in males.

3. The endocrine system communicates through chemical messengers called:

• A. Enzymes
• B. Hormones
• C. Antibodies
• D. Neurons

Correct answer: B

Rationale: The correct answer is B: Hormones. The endocrine system communicates through hormones, which are chemical messengers produced by glands and released into the bloodstream to target specific cells or organs in the body. Enzymes are biological molecules that catalyze biochemical reactions, antibodies are part of the immune system, and neurons are cells that transmit nerve impulses. In this context, enzymes, antibodies, and neurons do not play roles in the endocrine system's communication process, making them incorrect choices.

4. What is the body's primary defense against pathogens?

• A. Phagocytes
• B. Antibodies
• C. Memory B cells
• D. T lymphocytes

Correct answer: A

Rationale: The correct answer is A: Phagocytes. Phagocytes are the body's first line of defense against pathogens. They are innate immune cells that engulf and digest foreign particles like bacteria and viruses, preventing infections. Phagocytes act as the initial barrier to invading pathogens and are part of the innate immune response. Choice B, Antibodies, are produced by B cells in the adaptive immune response. Choice C, Memory B cells, are also part of the adaptive immune response and provide a faster and stronger response upon re-exposure to pathogens. Choice D, T lymphocytes, are part of the adaptive immune response, particularly involved in cell-mediated immunity.

5. What is the principle behind the phenomenon of refraction, where waves bend when entering a new medium?

• A. Change in wavelength
• B. Change in frequency
• C. Change in wave speed
• D. None of the above

Correct answer: C

Rationale: Refraction occurs due to a change in wave speed when waves enter a new medium. As waves travel from one medium to another, their speed changes, causing them to bend. This change in speed is responsible for the bending of waves during refraction. It is not the change in wavelength or frequency that causes refraction, but rather the change in speed as waves move through different mediums. Therefore, the correct answer is the change in wave speed (Choice C). Choices A and B are incorrect as refraction is not primarily influenced by changes in wavelength or frequency, but by changes in wave speed. Choice D is also incorrect as there is a specific principle, which is the change in wave speed, behind the phenomenon of refraction.

Similar Questions