Nursing Elites

1. Which of the following items is NOT a primary function of a healthy immune system?

• A. The immune system helps the body avoid infections.
• B. The immune system detects infections.
• C. The immune system eliminates infections.
• D. The immune system creates infections.

Correct answer: D

Rationale: The correct answer is D. The primary functions of a healthy immune system do not involve creating infections. A healthy immune system helps the body avoid infections by providing defense mechanisms, detects infections by recognizing harmful pathogens, and eliminates infections by attacking and clearing out pathogens. Creating infections goes against the protective role of the immune system and is not a function it performs. Therefore, choices A, B, and C are correct functions of a healthy immune system, while choice D is incorrect.

2. Based on the results that were stated, what would be a logical reason for some of the plants dying with the salt solution?

• A. Salt caused the plants to begin to dry up, leading to their death.
• B. The salt did not affect the plants.
• C. The salt provided adequate nutrients for growth.
• D. None of the above

Correct answer: A

Rationale: The most logical reason for some of the plants dying with the salt solution could be that salt caused the plants to begin to dry up, leading to their death. Excessive salt can disrupt the osmotic balance within plants, causing dehydration and ultimately death. Salt can create a hypertonic environment, drawing water out of plant cells and causing wilting and damage. Therefore, it is reasonable to assume that the presence of salt could have dried out some of the plants and caused them to die. Choices B and C are incorrect as the scenario presented indicates that the salt had a negative impact on the plants, causing some to die. Choice D is also incorrect as there is a valid reason provided for the plants dying due to the salt solution.

3. How many pairs of chromosomes are in a human cell?

• A. 46
• B. 23
• C. 64
• D. 32

Correct answer: B

Rationale: The correct answer is B: 23. Humans have 23 pairs of chromosomes, totaling 46 chromosomes. Each pair consists of one chromosome inherited from the mother and one from the father, making a total of 46 chromosomes in a human cell. Choice A (46) is incorrect as it represents the total number of chromosomes, not pairs. Choice C (64) and D (32) are incorrect as they do not reflect the accurate number of chromosome pairs in a human cell.

4. Which of the following is a true statement about dominance in genetics?

• A. All genes adhere to Mendel’s law of dominance.
• B. A dominant allele will always be expressed.
• C. When two dominant alleles are present, the resulting phenotype will express both traits.
• D. There are three or more alleles possible for all genes.

Correct answer: B

Rationale: In genetics, dominance refers to the relationship between two different alleles of a gene where one allele (dominant) masks the expression of another allele (recessive) in an individual's phenotype. The correct statement about dominance is that a dominant allele will always be expressed in the phenotype, even in the presence of a recessive allele. This means that if an individual has at least one dominant allele for a particular trait, that trait will be expressed. Choice A is incorrect because not all genes follow Mendel’s law of dominance; exceptions do exist. Choice C is incorrect because when two dominant alleles are present, only one will be expressed due to complete dominance. Choice D is incorrect as there can be more than three alleles for a gene, and not all genes have three or more alleles.

5. What is the primary function of the cell membrane?

• A. To provide structural support for the cell
• B. To transport substances in and out of the cell
• C. To synthesize proteins and lipids
• D. To store genetic material

Correct answer: B

Rationale: The primary function of the cell membrane, also known as the plasma membrane, is to regulate the movement of substances in and out of the cell. It acts as a selectively permeable barrier, allowing specific molecules to pass through while blocking others. This role is crucial for maintaining the internal environment of the cell by enabling essential nutrients to enter and waste products to exit. While the cell membrane provides some structural support for the cell, its main function is substance transport. Protein and lipid synthesis predominantly occur in organelles like the endoplasmic reticulum and Golgi apparatus, and storing genetic material is the nucleus's responsibility. Therefore, choices C (To synthesize proteins and lipids) and D (To store genetic material) are incorrect as these functions are carried out by other cell organelles, not the cell membrane.

Similar Questions