Nursing Elites

1. 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.

2. What is the process by which damaged muscle tissue repairs and rebuilds itself?

• A. Degeneration
• B. Regeneration
• C. Hyperplasia
• D. Metaplasia

Correct answer: B

Rationale: The correct answer is B: "Regeneration." Regeneration is the process by which damaged muscle tissue repairs and rebuilds itself by replacing the damaged cells with new, healthy cells. Degeneration refers to the deterioration of tissue, not the repair process. Hyperplasia is the increase in cell number, and metaplasia is the transformation of one cell type into another, neither of which directly relate to the repair process of damaged muscle tissue. Therefore, the most appropriate term for the described process is regeneration.

3. In which medium does light propagate at its highest speed?

• A. Air
• B. Water
• C. Glass
• D. Diamond

Correct answer: A

Rationale: The correct answer is A: 'Air.' Light propagates at its highest speed in a vacuum, which is nearly the same as in air. In a vacuum, light travels at its maximum speed of approximately 299,792 kilometers per second. When light enters a medium like air, water, glass, or diamond, its speed decreases due to interactions with atoms and molecules in the medium. Among the options given, air is the closest medium to a vacuum in terms of light speed. Water, glass, and diamond have higher refractive indices than air, causing light to travel slower in these mediums. This is why air allows light to propagate at its highest speed compared to water, glass, and diamond.

4. What is the primary function of ribosomes in the cell?

• A. To synthesize lipids and other cellular components
• B. To package and transport proteins
• C. To break down macromolecules
• D. To translate mRNA into proteins

Correct answer: D

Rationale: Rationale: Ribosomes are cellular organelles responsible for protein synthesis. They read the genetic information encoded in messenger RNA (mRNA) and use this information to assemble amino acids into a specific sequence, forming a protein. This process is known as translation and is essential for the production of proteins that carry out various functions in the cell. Options A, B, and C do not accurately describe the primary function of ribosomes in the cell.

5. A substance that can donate a hydroxide ion (OH-) in solution is classified as a:

• A. Salt
• B. Base
• C. Neutral compound
• D. Dehydrating agent

Correct answer: B

Rationale: Bases accept protons (H+) and can donate hydroxide ions

6. Which type of orbital can hold a maximum of 10 electrons?

• A. s orbital
• B. p orbital
• C. d orbital
• D. f orbital

Correct answer: D

Rationale: Each f orbital can hold up to 2 electrons, and there are 5 f orbitals, totaling a maximum of 10 electrons.

Similar Questions