Nursing Elites

1. The theory of evolution by natural selection suggests that:

• A. Organisms evolve towards perfection
• B. Traits are acquired through use and disuse
• C. Individuals with favorable traits survive and reproduce more
• D. All of the above

Correct answer: C

Rationale: Rationale: A) Organisms evolve towards perfection - This statement is incorrect. Evolution by natural selection does not suggest that organisms evolve towards perfection. Instead, it emphasizes the adaptation of organisms to their environment over time. B) Traits are acquired through use and disuse - This statement reflects Lamarck's theory of evolution, not Darwin's theory of evolution by natural selection. Lamarck proposed that organisms could acquire traits during their lifetime and pass them on to their offspring, which has been largely discredited. C) Individuals with favorable traits survive and reproduce more - This statement accurately reflects the central concept of Darwin's theory of evolution by natural selection. Individuals with traits that are advantageous in their environment are more likely to survive and reproduce, passing on those traits to future generations. D) All of the above - This option is incorrect because not all of the statements are true. Only option C a

2. The body's first line of defense against pathogens is the innate immune system. Which of the following is NOT a component of the innate immune system?

• A. Physical barriers like skin and mucous membranes
• B. Phagocytes that engulf and destroy pathogens
• C. Inflammatory response to isolate and contain infection
• D. Production of antibodies specific to a particular pathogen

Correct answer: D

Rationale: The innate immune system is the body's first line of defense against pathogens and includes physical barriers like skin and mucous membranes, phagocytes that engulf and destroy pathogens, and the inflammatory response to isolate and contain infection. However, the production of antibodies specific to a particular pathogen is a function of the adaptive immune system, not the innate immune system. The innate immune system provides immediate, nonspecific defenses, while the adaptive immune system generates specific responses to target pathogens. Therefore, option D is NOT a component of the innate immune system, making it the correct answer in this question.

3. What is the waxy or oily substance produced by sebaceous glands that helps lubricate the skin and hair?

• A. Keratin
• B. Melanin
• C. Sebum
• D. Sweat

Correct answer: C

Rationale: The correct answer is C: Sebum. Sebum is a waxy or oily substance produced by the sebaceous glands in the skin. It helps lubricate and waterproof the skin and hair, preventing them from drying out. Keratin is a protein found in the skin, hair, and nails, providing structure and strength. Melanin is a pigment that gives color to the skin, hair, and eyes. Sweat is produced by sweat glands and helps regulate body temperature by cooling the skin through evaporation. In this question, sebum specifically refers to the substance produced by sebaceous glands, making it the correct answer.

4. Which of the following is an example of stabilizing selection?

• A. Selection that favors extreme traits in a population
• B. Selection that removes individuals with extreme traits
• C. Selection that maintains the current average trait in a population
• D. Selection that favors one specific trait over all others

Correct answer: C

Rationale: Rationale: - Stabilizing selection is a type of natural selection that favors the intermediate variants in a population, while selecting against the extreme traits. This results in the maintenance of the current average trait in the population. - Option A is incorrect because stabilizing selection does not favor extreme traits; instead, it favors the average trait. - Option B is incorrect because stabilizing selection does not remove individuals with extreme traits; it acts against extreme traits by favoring the intermediate variants. - Option D is incorrect because stabilizing selection does not favor one specific trait over all others; it favors the average trait by selecting against extreme traits.

5. Which statement accurately defines power?

• A. Power is the amount of energy stored in an object
• B. Power is the rate at which energy is transferred or work is done
• C. Power is the maximum force exerted by an object
• D. Power is the resistance of an object to change in motion

Correct answer: b

Rationale: Power measures how quickly work is done or energy is transferred or converted.

6. The critical angle is defined as the minimum angle of incidence in a denser medium for which light undergoes:

• A. Total internal reflection
• B. Continued refraction
• C. Specular reflection
• D. Increased dispersion

Correct answer: A

Rationale: The critical angle is the minimum angle of incidence at which light is totally internally reflected rather than refracted. When light travels from a denser medium to a rarer medium at an angle greater than the critical angle, it undergoes total internal reflection. This phenomenon is crucial in applications like fiber optics and mirages. Continued refraction (option B) occurs when light enters a medium at an angle less than the critical angle. Specular reflection (option C) refers to the reflection of light at a smooth surface. Increased dispersion (option D) involves the separation of light into its constituent colors due to varying refractive indices, which is not directly related to the critical angle. Therefore, the correct answer is A - total internal reflection.

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