which of the following statements is true of mutations

HESI LPN

HESI Maternal Newborn

1. Which of the following statements is true of mutations?

A. Mutations can only occur by chance.
B. Mutations produce sperm and ova cells.
C. Mutations occur through radiation or other environmental influences.
D. Mutations help adenine combine with guanine to form the single spiral structure of DNA.

Correct answer: C

Rationale: The correct answer is C. Mutations can occur due to environmental influences such as radiation, chemicals, or other external factors, leading to changes in the DNA sequence. Choice A is incorrect because mutations can also occur due to errors in DNA replication, not solely by chance. Choice B is incorrect as mutations affect the DNA sequence itself, not the production of specific cells. Choice D is incorrect because mutations involve changes in the DNA sequence and do not specifically involve the formation of the DNA structure.

2. Which of the following most accurately describes the function of genes?

A. They regulate the development of traits.
B. They prevent foreign particles from entering the body.
C. They work together with lutein to influence development.
D. They transfer oxygen from the bloodstream to other parts of the body.

Correct answer: A

Rationale: The correct answer is A: 'They regulate the development of traits.' Genes play a crucial role in regulating the development of traits by encoding proteins that control various bodily functions and characteristics. This process involves gene expression and the production of proteins that ultimately determine an individual's traits. Choice B is incorrect because genes do not have a direct role in preventing foreign particles from entering the body; this function is primarily carried out by the immune system. Choice C is incorrect as genes do not specifically work with lutein to influence development; genes operate independently to regulate trait expression. Choice D is incorrect as genes are not responsible for transferring oxygen in the bloodstream; this function is carried out by red blood cells and hemoglobin.

3. Is color blindness a sex-linked abnormality?

A. TRUE
B. FALSE
C. Sometimes
D. Always

Correct answer: A

Rationale: The correct answer is A: TRUE. Color blindness is indeed a sex-linked abnormality as it is often associated with genes on the X chromosome. Since males have only one X chromosome, they are more likely to inherit color blindness if the gene is present. This makes color blindness more common in males. Choice B (FALSE) is incorrect because color blindness is linked to the X chromosome. Choices C (Sometimes) and D (Always) are incorrect as color blindness is consistently tied to the X chromosome.

4. A client is experiencing sore nipples from breastfeeding. Which of the following actions should the nurse take?

A. Place a snug dressing on the client’s nipple when not breastfeeding
B. Ensure the newborn’s mouth is wide open before latching to the breast
C. Encourage the client to limit the newborn’s feeding to 10 minutes on each breast
D. Instruct the client to begin the feeding with the nipple that is most tender

Correct answer: B

Rationale: Ensuring the newborn's mouth is wide open before latching is crucial for achieving a proper latch, which can help reduce nipple soreness. Placing a snug dressing on the nipple when not breastfeeding (choice A) can lead to further irritation and hinder healing. Encouraging the client to limit the newborn’s feeding to 10 minutes on each breast (choice C) may not be adequate for effective feeding as infants should feed until they are satisfied. Instructing the client to begin feeding with the most tender nipple (choice D) can worsen the soreness as it may not allow the baby to feed effectively.

5. Which of the following statements is a symptom of cystic fibrosis in children?

A. Cystic fibrosis leads to uncontrollable muscle movements and personality changes.
B. Cystic fibrosis leads to the excessive production of thick mucus that clogs the pancreas and lungs.
C. Cystic fibrosis causes red blood cells to clump together, obstructing small blood vessels and decreasing the oxygen supply.
D. Cystic fibrosis causes the central nervous system to degenerate, resulting in death.

Correct answer: B

Rationale: The correct answer is B. Cystic fibrosis is a genetic disorder that causes the body to produce thick, sticky mucus. This mucus can clog the airways in the lungs and obstruct the pancreas, leading to severe respiratory and digestive problems. Choice A is incorrect because uncontrollable muscle movements and personality changes are not typical symptoms of cystic fibrosis. Choice C is incorrect because cystic fibrosis does not directly cause red blood cells to clump together and obstruct small blood vessels. Choice D is incorrect because cystic fibrosis primarily affects the respiratory and digestive systems, not the central nervous system.