Nursing Elites

1. Which of the following basic mechanisms of evolution is described as the process where organisms with an advantageous trait survive more often and produce more offspring than organisms without the advantageous trait?

• A. gene flow
• B. genetic drift
• C. mutation
• D. natural selection

Correct answer: D

Rationale: Natural selection is the basic mechanism of evolution that explains how organisms with advantageous traits are more likely to survive and reproduce in a given environment. This leads to the passing on of these favorable traits to their offspring, causing these traits to become more common in the population over time, resulting in evolutionary change. Natural selection is driven by environmental pressures that support the survival and reproduction of individuals with specific traits. Gene flow refers to the movement of genes between populations, genetic drift is the change in allele frequencies due to random events, and mutation is the source of genetic variation but is not the process by which advantageous traits become more prevalent in a population.

2. 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: The correct answer is the f orbital. Each f orbital can hold up to 2 electrons. Since there are 5 f orbitals, the total maximum number of electrons that can be accommodated in f orbitals is 10 (2 electrons per orbital x 5 orbitals = 10 electrons). Therefore, the f orbital can hold a maximum of 10 electrons. Choice A, s orbital, is incorrect because it can hold a maximum of 2 electrons. Choice B, p orbital, is incorrect because it can hold a maximum of 6 electrons (3 orbitals x 2 electrons per orbital = 6 electrons). Choice C, d orbital, is incorrect as it can hold a maximum of 10 electrons (5 orbitals x 2 electrons per orbital = 10 electrons), but the question asks for the type of orbital that can hold a maximum of 10 electrons, not the total number of electrons in d orbitals.

3. Which of the following is responsible for carrying oxygenated blood from the heart to the body?

• A. Vein
• B. Artery
• C. Capillary
• D. Lymphatic vessel

Correct answer: B

Rationale: The correct answer is B: Artery. Arteries carry oxygenated blood away from the heart to the body. Veins carry deoxygenated blood back to the heart, capillaries are tiny blood vessels where gas exchange occurs, and lymphatic vessels are part of the lymphatic system, which is responsible for draining excess fluid from tissues and transporting white blood cells.

4. Why are negative feedback mechanisms crucial in the endocrine system?

• A. To increase hormone production continuously
• B. To maintain hormone levels within a specific range
• C. To cause a constant release of hormones
• D. To disrupt communication between glands

Correct answer: B

Rationale: Negative feedback mechanisms in the endocrine system play a vital role in maintaining hormone levels within a specific range. When hormone levels deviate from the set point, negative feedback signals prompt adjustments in hormone production to bring the levels back to the optimal range. This process ensures a delicate balance of hormones in the body, preventing excesses or deficiencies. Choice A is incorrect because continuously increasing hormone production would lead to imbalances. Choice C is incorrect as a constant release of hormones without regulation would disrupt homeostasis. Choice D is incorrect because disrupting communication between glands would hinder proper coordination and regulation of hormone levels, which is essential for the body's overall function.

5. Which of the following statements about prions is TRUE?

• A. They are composed of proteins only
• B. They are easily destroyed by common disinfectants
• C. hey are a type of antibiotic
• D. They are a live organism

Correct answer: A

Rationale: A) This statement is true. Prions are infectious agents composed entirely of protein, lacking nucleic acids such as DNA or RNA. They are known for causing neurodegenerative diseases in animals and humans. B) This statement is false. Prions are not easily destroyed by common disinfectants due to their unique structure and resistance to conventional sterilization methods. C) This statement is false. Prions are not a type of antibiotic. They are a distinct class of infectious agents. D) This statement is false. Prions are not live organisms but rather misfolded proteins that can induce abnormal folding in normal proteins, leading to disease.

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