Nursing Elites

1. What is the process by which a population gradually loses genetic variation?

• A. Founder effect
• B. Bottleneck effect
• C. Gene flow
• D. Speciation

Correct answer: B

Rationale: A) Founder effect: This occurs when a small group of individuals establishes a new population, leading to a loss of genetic variation compared to the original population. It does not necessarily result in a gradual loss of genetic variation in an existing population. B) Bottleneck effect: This process occurs when a population is drastically reduced in size, leading to a significant loss of genetic variation due to the limited number of individuals contributing to the gene pool. The reduced genetic diversity can have long-term effects on the population's ability to adapt to environmental changes. C) Gene flow: This refers to the movement of genes between populations, which can introduce new genetic variation and prevent populations from diverging. Gene flow does not lead to a gradual loss of genetic variation within a population. D) Speciation: This is the process by which new species evolve from existing species, often involving the accumulation of genetic differences that l

2. Which of the following is LEAST likely to be found in a human cell's genes?

• A. Sequences of amino acids to be transcribed into mRNA
• B. Lethal recessive traits like sickle cell anemia
• C. Mutated DNA
• D. DNA that codes for proteins the cell doesn't use

Correct answer: D

Rationale: Human cells typically contain genes that code for proteins necessary for the cell's functions. DNA that codes for proteins the cell doesn't use would be an inefficient use of the cell's resources. Therefore, it is less likely to be found in a human cell's genes. Options A, B, and C are more commonly associated with genes found in human cells. Choice A refers to the genetic information needed for protein synthesis, while choice B involves traits that can be present in the gene pool. Mutated DNA (choice C) can also be found in human cells as a result of genetic alterations. However, DNA that codes for proteins not utilized by the cell would be redundant and not typically retained in the genome.

3. What is the most basic unit of structure in living things?

• A. Cell
• B. Organelle
• C. Oxygen
• D. Pigment

Correct answer: A

Rationale: The cell is indeed the most basic unit of life, forming the foundation of all living organisms. Cells are the building blocks of all living things, containing organelles that perform specific functions. While oxygen is essential for life, it is not a structural unit. Similarly, pigment is a component found within cells but is not the fundamental unit of structure. Therefore, the correct answer is 'A: Cell.'

4. What might happen if blood sugar begins to drop in the human body?

• A. The pancreas releases insulin.
• B. The liver releases stored glucose.
• C. The liver stores glucose as glycogen.
• D. The pancreas releases glucagon.

Correct answer: D

Rationale: When blood sugar levels drop in the body, the pancreas releases glucagon. Glucagon acts to increase blood sugar levels by stimulating the liver to release stored glucose into the bloodstream. Therefore, the correct answer is D. Choice A is incorrect because the release of insulin lowers blood sugar levels, opposite of what happens when blood sugar is dropping. Choice B is incorrect as the liver releases stored glucose in response to low blood sugar, not when blood sugar is already dropping. Choice C is also incorrect as the liver stores glucose as glycogen but doesn't directly impact blood sugar levels dropping in the moment.

5. How is blood pressure controlled by the body?

• A. By adjusting heart rate only
• B. By regulating blood volume
• C. By baroreceptors and hormones
• D. By adjusting body temperature

Correct answer: C

Rationale: Blood pressure is controlled by baroreceptors located in the aortic arch and carotid arteries that detect changes in blood pressure levels. When blood pressure is high, these receptors signal for adjustments to lower it. Additionally, hormones such as renin from the kidneys are released when blood pressure drops, further aiding in blood pressure regulation. Choice A is incorrect because blood pressure regulation involves more than just adjusting heart rate; it also includes vasodilation and vasoconstriction. Choice B is incorrect as while blood volume can impact blood pressure, it is not the primary mechanism of blood pressure control. Choice D is incorrect as body temperature regulation is a separate physiological process and not directly related to blood pressure control.

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