Nursing Elites

1. Which of the following is a unit of work and energy?

• A. Pascal (Pa)
• B. Kilowatt-hour (kWh)
• C. Coulomb (C)
• D. Tesla (T)

Correct answer: b

Rationale: Kilowatt-hour is a unit used to measure both work and energy, especially in the context of electricity consumption.

2. What is the shape of the DNA molecule?

• A. Linear
• B. Circular
• C. Double helix
• D. Straight chain

Correct answer: C

Rationale: Rationale: The shape of the DNA molecule is a double helix. This structure was first described by James Watson and Francis Crick in 1953. The double helix shape consists of two strands that are twisted around each other in a spiral. This shape allows DNA to be compactly stored within the cell nucleus and provides stability to the molecule. The other options (A) Linear, (B) Circular, and (D) Straight chain do not accurately describe the shape of the DNA molecule.

3. A keystone species plays a critical role in an ecosystem because its removal would:

• A. Lead to a decrease in competition among other species
• B. Cause a slight increase in primary productivity
• C. Have a minimal impact on the overall ecosystem structure
• D. Disrupt the food web and cause cascading effects on other populations

Correct answer: D

Rationale: Rationale: Keystone species are species that have a disproportionately large effect on their environment relative to their abundance. They play a critical role in maintaining the structure and function of an ecosystem. If a keystone species is removed from an ecosystem, it can disrupt the food web by causing imbalances in predator-prey relationships. This disruption can lead to cascading effects on other populations within the ecosystem, potentially causing population declines or even extinctions. Therefore, the removal of a keystone species would have significant impacts on the overall ecosystem structure, making option D the correct answer.

4. Which hormone, produced by the adrenal glands, helps regulate the body's response to stress, including increasing blood pressure and suppressing the immune system?

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

Correct answer: c

Rationale: The correct answer is C: Cortisol. Cortisol is a hormone produced by the adrenal glands that plays a crucial role in the body's response to stress. It helps regulate blood pressure by increasing it to prepare the body for stressors. Additionally, cortisol suppresses the immune system to prioritize the stress response. Aldosterone, while also produced by the adrenal glands, primarily regulates electrolyte balance and blood pressure. Epinephrine, produced by the adrenal medulla, is involved in the fight-or-flight response but does not suppress the immune system like cortisol. Insulin, produced by the pancreas, regulates blood sugar levels and is not directly involved in the stress response. Therefore, Cortisol is the hormone that specifically helps regulate the body's response to stress by increasing blood pressure and suppressing the immune system.

5. Which of the following is a property of amphiprotic substances?

• A. React with acids only
• B. React with bases only
• C. Can act as both acids and bases
• D. Are inert in chemical reactions

Correct answer: C

Rationale: Amphiprotic substances can donate or accept a proton, so they can act as both acids and bases. The other choices do not accurately describe amphiprotic substances.

6. Osteoporosis is a condition leading to weakened bones and increased risk of fractures. Which hormone plays a key role in bone health and is often affected in osteoporosis?

• A. Estrogen
• B. Testosterone
• C. Thyroid hormone
• D. Insulin

Correct answer: A

Rationale: Estrogen plays a crucial role in bone health by promoting the activity of bone-forming cells and inhibiting bone breakdown. In women, estrogen levels decrease significantly during menopause, leading to a higher risk of osteoporosis. This hormone helps maintain bone density and strength, making it essential for preventing bone loss and fractures. Testosterone, while important for overall health, does not have as significant of an impact on bone health as estrogen does. Thyroid hormone and insulin also have roles in the body, but they are not as directly linked to bone health as estrogen. Therefore, the correct answer is A: Estrogen.

Similar Questions