Nursing Elites

1. _____ are environmental agents that can harm the embryo or fetus.

• A. Mutations
• B. Autosomes
• C. Teratogens
• D. Androgens

Correct answer: C

Rationale: Teratogens are environmental agents, such as drugs, chemicals, or infections, that can cause harm to a developing embryo or fetus. Mutations (Choice A) refer to changes in the DNA sequence and are not environmental agents. Autosomes (Choice B) are chromosomes that are not involved in determining an individual's sex and are not environmental agents that harm the embryo or fetus. Androgens (Choice D) are a group of hormones that are more related to male sexual development and function, not environmental agents that harm the embryo or fetus.

2. The _____ is the inner layer of the embryo from which the lungs and digestive system develop.

• A. neural tube
• B. mesoderm
• C. endoderm
• D. umbilical cord

Correct answer: C

Rationale: The endoderm is the correct answer. It is the innermost layer of the embryo that gives rise to organs such as the lungs, digestive system, liver, and pancreas. The neural tube (Choice A) forms the brain and spinal cord, not the lungs or digestive system. Mesoderm (Choice B) develops into structures like muscles, bones, and circulatory system, not the lungs or digestive system. The umbilical cord (Choice D) serves as a connection between the embryo and the placenta, providing nutrients and oxygen, but it is not the layer from which lungs and digestive system develop.

3. Rico is a man who has enlarged breasts and suffers from mild mental retardation. He has a problem learning languages, and his body produces less of the male sex hormone testosterone than normal males. Rico is most likely suffering from:

• A. Klinefelter syndrome.
• B. Tay-Sachs disease.
• C. Turner syndrome.
• D. Down syndrome.

Correct answer: A

Rationale: Rico's symptoms align with Klinefelter syndrome, which is characterized by an extra X chromosome in males (XXY). Enlarged breasts (gynecomastia), mild mental retardation, learning difficulties, and reduced testosterone production are common features of Klinefelter syndrome. Choice B, Tay-Sachs disease, is a genetic disorder that affects the nervous system and is not associated with the symptoms described. Choice C, Turner syndrome, occurs in females with a missing or partially missing X chromosome and does not fit Rico's profile. Choice D, Down syndrome, is caused by an extra copy of chromosome 21 and typically does not present with the symptoms mentioned for Rico.

4. According to a study conducted in 2013 by Fellman, what affects the chances of having twins?

• A. Increase when a woman conceives at a younger age.
• B. Increase with parental age.
• C. Decrease with the frequency of intercourse before conception.
• D. Decrease with the use of fertility drugs.

Correct answer: B

Rationale: The correct answer is B. According to the study by Fellman in 2013, the chances of having twins actually increase with parental age. Choice A is incorrect as the study does not specify a younger age for conceiving to increase the chances of twins. Choice C is incorrect as the frequency of intercourse before conception is not a highlighted factor in the study. Choice D is also incorrect as the study does not discuss the impact of fertility drugs on the likelihood of having twins.

5. What is the primary role of meiosis in the production of sperm and ova?

• A. To reduce the chromosome number by half
• B. To increase the chromosome number
• C. To create identical copies of chromosomes
• D. To repair damaged chromosomes

Correct answer: A

Rationale: The correct answer is A. Meiosis is a type of cell division that reduces the chromosome number by half, resulting in the formation of sperm and ova. Choice B is incorrect because meiosis does not increase the chromosome number. Choice C is incorrect because meiosis creates genetically diverse gametes, not identical copies of chromosomes. Choice D is incorrect because meiosis does not primarily function to repair damaged chromosomes.

Similar Questions