Nursing Elites

1. Which structure in the skin is responsible for producing melanin?

• A. Sudoriferous gland
• B. Melanocyte
• C. Sebaceous gland
• D. Hair follicle

Correct answer: B

Rationale: The correct answer is B: Melanocyte. Melanocytes in the skin are responsible for producing melanin, the pigment that gives skin its color and provides protection against harmful UV radiation. Sudoriferous glands produce sweat, sebaceous glands produce sebum (oil), and hair follicles are associated with hair growth. However, the specific function of producing melanin is attributed to melanocytes, making them the correct answer in this context.

2. What is a monohybrid cross, and what is the ratio of dominant to recessive gene manifestation?

• A. A cross involving two traits, 9:3:3:1
• B. A cross involving one trait, 3:1
• C. A cross involving two traits, 1:2:1
• D. A cross involving one trait, 1:1

Correct answer: B

Rationale: A monohybrid cross is a genetic cross involving one trait. The ratio of dominant to recessive gene manifestation in the offspring is typically 3:1 when both parents are heterozygous. This ratio is the genotypic ratio, not just the phenotype ratio, where the dominant allele is present in 3 out of 4 offspring, and the recessive allele is present in 1 out of 4 offspring. Choice A is incorrect because it describes a dihybrid cross ratio. Choice C is incorrect as it represents the genotypic ratio for a monohybrid cross involving incomplete dominance. Choice D is incorrect as it does not reflect the typical ratio for a monohybrid cross.

3. How are the frequency and wavelength of a wave related?

• A. Inversely proportional
• B. Directly proportional
• C. No relationship
• D. Dependent on the medium

Correct answer: A

Rationale: The correct answer is that the frequency and wavelength of a wave are inversely proportional. This relationship is defined by the wave equation: speed = frequency x wavelength. When the frequency of a wave increases, its wavelength decreases, and vice versa. This means that as one quantity increases, the other decreases in a consistent manner, illustrating an inverse relationship between frequency and wavelength. Choice B, 'Directly proportional,' is incorrect because an increase in frequency does not lead to an increase in wavelength; they move in opposite directions. Choice C, 'No relationship,' is incorrect as frequency and wavelength are interconnected as described above. Choice D, 'Dependent on the medium,' is incorrect because the relationship between frequency and wavelength is a fundamental property of waves and is not solely determined by the medium through which the wave propagates.

4. How do isotopes affect the atomic mass of an element?

• A. Isotopes have no effect on the atomic mass of an element.
• B. Isotopes cause the atomic mass of an element to vary slightly.
• C. Isotopes cause the atomic mass of an element to be exactly the same for all isotopes of that element.
• D. Isotopes cause the atomic mass of an element to vary greatly.

Correct answer: B

Rationale: Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. Since the atomic mass of an element is the weighted average of the masses of its isotopes, the presence of isotopes causes the atomic mass of an element to vary slightly. This variation occurs because different isotopes have different masses due to their varying numbers of neutrons. The atomic mass is affected by the abundance of each isotope, leading to a slight fluctuation in the overall atomic mass of the element. Choice A is incorrect because isotopes do influence the atomic mass. Choice C is incorrect because isotopes have different masses, affecting the overall atomic mass. Choice D is incorrect as isotopes typically do not cause a significant variation in atomic mass, but rather a slight fluctuation.

5. What does the term 'dilution' refer to in a solution?

• A. Adding more solvent to decrease concentration
• B. Adding more solute to increase concentration
• C. Reducing the temperature to increase solubility
• D. Increasing pressure to increase solubility

Correct answer: A

Rationale: The term 'dilution' in a solution refers to adding more solvent to decrease the concentration of the solution. Dilution involves reducing the concentration of the solute in the solution by increasing the amount of solvent. Choice B is incorrect because adding more solute would increase the concentration, not decrease it. Choices C and D are also incorrect as they relate to factors affecting solubility, not dilution specifically. Therefore, choice A is the correct answer as it accurately defines the process of dilution in a solution.

Similar Questions