Nokea
What is the point after which an ovum is fertilized and becomes impenetrable to any other sperm?
- A. The zona reaction
- B. Gametogenesis
- C. The zona pellucida
- D. Cleavage
Correct Answer: A
Rationale: The correct answer is A: The zona reaction. After fertilization, the zona pellucida undergoes a biochemical change called the zona reaction, which makes the ovum impenetrable to any other sperm. This process prevents polyspermy and ensures that only one sperm can fertilize the egg. Gametogenesis refers to the production of gametes, not the post-fertilization event. The zona pellucida is the glycoprotein layer around the ovum, and cleavage is the rapid mitotic cell division that follows fertilization, but neither of these directly relate to the ovum becoming impenetrable to other sperm.
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Identify the health care provided during a home birth. Select all that apply.
- A. labor support
- B. trained birth attendant
- C. neonatal intensive care
- D. breast-feeding assistance
Correct Answer: C
Rationale: The correct answer is C: neonatal intensive care. This is because during a home birth, neonatal intensive care is not provided as it requires specialized medical equipment and expertise typically only available in hospitals. Labor support (A) and trained birth attendant (B) are essential for home births. Breastfeeding assistance (D) may be provided post-birth but is not a defining feature of care during a home birth.
After counseling with an obstetrician about infertility, a couple is advised to undergo testicular sperm aspiration. The nurse is aware that the procedure may be recommended for which infertility?
- A. Blocked fallopian tubes
- B. Unsuccessful vasectomy reversal
- C. Poor cervical mucus production
- D. Diminished sperm motility
Correct Answer: B
Rationale: Step 1: Testicular sperm aspiration is a procedure to retrieve sperm directly from the testicles.
Step 2: If a vasectomy reversal was unsuccessful, it means there is no sperm in the ejaculate due to the blocked vas deferens.
Step 3: Testicular sperm aspiration can be recommended in such cases to retrieve sperm for assisted reproductive techniques.
Summary:
A: Blocked fallopian tubes do not involve male infertility; they affect female fertility.
C: Poor cervical mucus production is a female factor, not male.
D: Diminished sperm motility may require other treatments, not testicular sperm aspiration.
The nurse is assessing the knowledge of new parents with a child born with maple syrup urine disease (MSUD). This is an autosomal recessive inherited disorder, which means that:
- A. Both genes of a pair must be abnormal for the disorder to be expressed.
- B. Only one copy of the abnormal gene is required for the disorder to be expressed.
- C. The disorder occurs in males and heterozygous females.
- D. The disorder is carried on the X chromosome.
Correct Answer: A
Rationale: MSUD is a type of autosomal recessive inheritance disorder in which both genes of a pair must be abnormal for the disorder to be expressed.
Which statement best describes the changes that occur during the fetal period of development?
- A. Maturation of organ systems
- B. Development of basic organ systems
- C. Resistance of organs to damage from external agents
- D. Development of placental oxygen–carbon dioxide exchange
Correct Answer: A
Rationale: The correct answer is A because during the fetal period, organ systems continue to mature and develop to become fully functional. This includes refining the structures and functions of organs that have already been formed during the embryonic period. Option B is incorrect because basic organ systems are already formed during the embryonic period. Option C is incorrect as organs are still susceptible to damage during the fetal period. Option D is incorrect because the development of placental oxygen–carbon dioxide exchange primarily occurs during the early stages of pregnancy, not specifically during the fetal period.
The measurement of lecithin in relation to sphingomyelin (L/S ratio) is used to determine fetal lung maturity. Which ratio reflects maturity of the lungs?
- A. 1.4:1
- B. 1.8:1
- C. 2:01
- D. 1:01
Correct Answer: C
Rationale: A ratio of 2:1 indicates lung maturity.