Nursing Elites

1. Which hormone is responsible for regulating sleep-wake cycles and is influenced by light exposure?

• A. Melatonin
• B. Cortisol
• C. Estrogen
• D. Glucagon

Correct answer: A

Rationale: The correct answer is A: Melatonin. Melatonin is a hormone produced by the pineal gland in the brain and plays a crucial role in regulating the sleep-wake cycle, also known as the circadian rhythm. Melatonin levels typically rise in the evening in response to darkness and help signal to the body that it's time to sleep. Exposure to light, especially blue light, can inhibit the production of melatonin, making us more alert and awake. Cortisol (option B) is a stress hormone that helps regulate metabolism and immune response. Estrogen (option C) is a female sex hormone, and glucagon (option D) is a hormone that increases blood sugar levels. Therefore, the hormone responsible for regulating sleep-wake cycles and influenced by light exposure is melatonin.

2. Which muscle type is characterized by a combination of voluntary and involuntary control, is striated, and is responsible for pumping blood throughout the circulatory system?

• A. Skeletal muscle
• B. Smooth muscle
• C. Cardiac muscle
• D. Connective tissue

Correct answer: c

Rationale: The correct answer is C: Cardiac muscle. Cardiac muscle is characterized by a combination of voluntary and involuntary control, as the heart can beat involuntarily while also responding to signals from the autonomic nervous system. It is striated, meaning it has a striped appearance under a microscope due to the arrangement of contractile proteins. Cardiac muscle is responsible for pumping blood throughout the circulatory system, making it crucial for maintaining circulation and delivering oxygen and nutrients to tissues. Skeletal muscle (option A) is primarily under voluntary control and is responsible for movement, while smooth muscle (option B) is predominantly involuntarily controlled and found in organs like the intestines. Connective tissue (option D) provides support and structure but is not a muscle type responsible for pumping blood.

3. Acne vulgaris, commonly known as acne, is primarily caused by

• A. Dry skin (Dry skin can worsen acne but isn't the primary cause)
• B. Clogged pores and excess oil production
• C. Bacterial infection alone (Bacteria play a role but not the sole cause)
• D. Vitamin deficiency

Correct answer: B

Rationale: The correct answer is B: 'Clogged pores and excess oil production.' Acne vulgaris, or acne, is primarily caused by a combination of factors including excess sebum (oil) production by the skin's sebaceous glands and the accumulation of dead skin cells, leading to clogged pores. This environment provides a breeding ground for acne-causing bacteria, contributing to inflammation and the formation of pimples. While factors like dry skin, bacterial infections, and even vitamin deficiencies can exacerbate acne, they are not the primary cause. Thus, B is the most accurate option for the primary cause of acne.

4. The process by which a solid changes directly into a liquid is called:

• A. Melting
• B. Condensation
• C. Sublimation
• D. Deposition

Correct answer: D

Rationale: While melting is a solid to liquid transition, deposition, also known as sublimation, refers to a gas directly changing into a solid.

5. The word "obscurity" can be replaced with which of the following without changing the meaning?

• A. Prominence
• B. Seclusion
• C. Destruction
• D. Transformation

Correct answer: B

Rationale: Both "obscurity" and "seclusion" imply being hidden or unknown. Prominence, destruction, and transformation do not convey the same meaning.

6. A set of integers can be classified as positive, negative, or zero. Which of the following statements about multiplying positive and negative integers is ALWAYS true?

• A. The product will always be positive.
• B. The product will always be negative.
• C. The product will depend on the specific positive and negative numbers used.
• D. Positive and negative integers cannot be multiplied

Correct answer: B

Rationale: Rationale: When multiplying a positive integer by a negative integer, the product will always be negative. This is a fundamental rule of arithmetic. The sign of the product is determined by the rule that states that a positive number multiplied by a negative number results in a negative number. Therefore, the statement that the product will always be negative is always true when multiplying positive and negative integers.

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