Nursing Elites

1. Does a blastocyst gain mass only when it receives nourishment from outside?

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

Correct answer: A

Rationale: A blastocyst does indeed require external nourishment from the mother's body to continue developing and gaining mass. Without this external nourishment, the blastocyst would not be able to grow and develop properly. Therefore, the statement that a blastocyst gains mass only when it receives nourishment from outside is true. Choices B, C, and D are incorrect because they do not accurately reflect the dependency of a blastocyst on external nourishment for its development and growth.

2. Before meiosis, a sperm cell:

• A. contains 46 chromosomes.
• B. contains two X chromosomes.
• C. is significantly larger than an egg cell.
• D. contains both an X and a Y chromosome.

Correct answer: A

Rationale: Before meiosis, a sperm cell contains 46 chromosomes. This is because sperm cells, like other somatic cells, have a diploid number of chromosomes. During meiosis, the number of chromosomes is halved to 23 to combine with an egg cell during fertilization. Choice B is incorrect because a sperm cell carries either an X or a Y chromosome, not both (Choice D). Choice C is incorrect as sperm cells are generally smaller than egg cells, which is an adaptation that aids in motility and penetration of the egg during fertilization.

3. Are sperm much larger than ova?

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

Correct answer: B

Rationale: The correct answer is B: FALSE. Ova, also known as eggs, are actually the largest cells in the human body, while sperm are significantly smaller. This size difference is due to the different functions of the two gametes. Sperm are specialized for motility to reach and fertilize the egg, while ova contain nutrients and cellular machinery needed for fertilization and early embryonic development. Choices A, C, and D are incorrect because sperm are not larger than ova; they are much smaller in size.

4. Which synthetic hormone is used to prevent miscarriages and can cause masculinization of the fetus?

• A. Testosterone
• B. Estrogen
• C. Progestin
• D. Oxytocin

Correct answer: C

Rationale: Progestin is the synthetic hormone used to prevent miscarriages. While it is beneficial in maintaining pregnancy, in some cases, it can lead to masculinization of the fetus. Testosterone (Choice A) and estrogen (Choice B) are not typically used to prevent miscarriages and do not cause masculinization of the fetus in this context. Oxytocin (Choice D) is a hormone involved in labor and breastfeeding, but it is not used to prevent miscarriages nor does it cause masculinization of the fetus.

5. The _________ is the hollow organ within females in which the embryo and fetus develop.

• A. placenta
• B. ovum
• C. uterus
• D. amniotic sac

Correct answer: C

Rationale: The correct answer is C: uterus. The uterus is the organ where the embryo implants and the fetus develops during pregnancy. The placenta (choice A) is an organ that develops during pregnancy and provides nutrients and oxygen to the fetus, but it is not the organ where the embryo and fetus physically develop. The ovum (choice B) is the female reproductive cell or egg that is fertilized by the sperm to form an embryo, but it is not the organ where the embryo and fetus develop. The amniotic sac (choice D) is a membrane filled with amniotic fluid that surrounds and protects the fetus, but it is not the organ where the embryo and fetus physically develop.

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