HESI LPN
HESI Maternity 55 Questions
1. The embryo and fetus develop within a protective _______ in the uterus.
- A. amniotic sac
- B. umbilical cord
- C. neural tube
- D. embryonic disk
Correct answer: A
Rationale: The correct answer is A, the amniotic sac. The amniotic sac is a fluid-filled structure that surrounds and protects the developing embryo and fetus in the uterus. It provides a cushion against external pressure, allows for movement and growth, and helps maintain a stable environment for the developing fetus. Choices B, C, and D are incorrect. The umbilical cord connects the fetus to the placenta and serves as a conduit for nutrients and waste; the neural tube is a structure that forms the central nervous system in early embryonic development; and the embryonic disk is a structure that forms during gastrulation, one of the early stages of embryonic development.
2. How many pairs of autosomes does a human zygote contain?
- A. 46
- B. 44
- C. 23
- D. 22
Correct answer: D
Rationale: A human zygote contains 22 pairs of autosomes and one pair of sex chromosomes, totaling 46 chromosomes. Therefore, the correct answer is 22. Choices A, B, and C are incorrect because they do not accurately represent the number of autosomes in a human zygote. Option A (46) represents the total number of chromosomes in a human zygote, not the number of autosomes. Option B (44) is incorrect as it does not account for the correct number of autosomes. Option C (23) is inaccurate since it represents the total number of chromosomes in a human gamete, not the number of autosomes in a zygote.
3. Females with Turner syndrome:
- A. possess more thymine than cytosine.
- B. are taller than average.
- C. produce little estrogen.
- D. are more likely to give birth to twins.
Correct answer: C
Rationale: Turner syndrome is a chromosomal disorder in females characterized by short stature and underdeveloped ovaries, resulting in low estrogen production. This leads to symptoms such as delayed puberty and infertility. Choice A is incorrect because the chromosomal abnormality in Turner syndrome does not affect the thymine-cytosine ratio. Choice B is incorrect as females with Turner syndrome are typically shorter than average. Choice D is incorrect as Turner syndrome does not increase the likelihood of giving birth to twins.
4. Once the testes have developed in the embryo, they begin to produce male sex hormones, or _____.
- A. androgens
- B. genotypes
- C. blastocysts
- D. teratogens
Correct answer: A
Rationale: Androgens are male sex hormones, such as testosterone, produced by the testes after they have developed in the embryo. Androgens are responsible for the development of male secondary sexual characteristics. Genotypes refer to an individual's genetic makeup, not hormones. Blastocysts are early stage embryos, not male sex hormones. Teratogens are substances that can interfere with fetal development, not male sex hormones produced by the testes.
5. How many chromosomes are typically found in human cells, organized into pairs?
- A. 50
- B. 46
- C. 48
- D. 44
Correct answer: B
Rationale: Human cells typically contain 46 chromosomes organized into 23 pairs. This is the correct number for a normal human cell. Choices A, C, and D are incorrect because they do not represent the typical chromosome count in human cells.
Similar Questions
Access More Features
HESI LPN Basic
$69.99/ 30 days
- 5,000 Questions with answers
- All HESI courses Coverage
- 30 days access
HESI LPN Premium
$149.99/ 90 days
- 5,000 Questions with answers
- All HESI courses Coverage
- 30 days access