Nokea
Which of the following is the male pattern of development “master switch” gene?
- A. SRY
- B. MIS
- C. XYY
- D. XXY
Correct Answer: A
Rationale: The correct answer is A: SRY. The Sex-determining Region Y (SRY) gene is the master switch for male development. It initiates the development of male gonads. Choice B, MIS, is a hormone involved in female reproductive development. Choices C and D, XYY and XXY, are genetic conditions related to male chromosomal variations and are not the master switch gene for male development.
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A nurse teaches a male client how to perform a testicular self-exam in an effort to identify lumps that may be present in the testes. What does the nurse teach the client regarding normal testes size?
- A. Both testes should be the same size
- B. One testis is usually larger than the other
- C. One testis usually has a lump; the other does not
- D. Both testes usually have lumps
Correct Answer: B
Rationale: It is normal for one testicle to be slightly larger than the other.
The ejaculatory duct is the union of the vas deferens and _____.
- A. seminal vesicle
- B. prostate
- C. ampulla
- D. urethra
Correct Answer: A
Rationale: The correct answer is A: seminal vesicle. The ejaculatory duct is formed by the union of the vas deferens and the seminal vesicle. The seminal vesicle contributes seminal fluid that mixes with sperm from the vas deferens to form semen. The prostate gland surrounds the ejaculatory duct but does not directly join it. The ampulla is an enlarged portion of the vas deferens but does not directly connect to the ejaculatory duct. The urethra is the tube that carries urine and semen out of the body but is not part of the ejaculatory duct. Therefore, the correct answer is A because the seminal vesicle directly joins with the vas deferens to form the ejaculatory duct.
Braxton Hicks contractions are a sign
- A. progesterone of
- B. oxytocin
- C. parturition.
- D. childbirth.
Correct Answer: B
Rationale: The correct answer is B: oxytocin. Braxton Hicks contractions are irregular, painless contractions of the uterus that occur throughout pregnancy. Oxytocin is the hormone responsible for stimulating contractions during labor. Therefore, the presence of Braxton Hicks contractions indicates the preparation of the uterus for labor under the influence of oxytocin. Choices A, C, and D are incorrect as they do not directly relate to the physiological mechanism of Braxton Hicks contractions.
The primitive stem cell of spermatogenesis, which is found on the periphery of each seminiferous tubule, is called a ________.
- A. spermatogonium
- B. spermatid
- C. primary spermatocyte
- D. secondary spermatocyte
Correct Answer: A
Rationale: The correct answer is A: spermatogonium. Spermatogonium is the primitive stem cell of spermatogenesis located at the periphery of seminiferous tubules. It undergoes mitosis to produce more spermatogonia or differentiate into primary spermatocytes. Spermatid and secondary spermatocyte are later stages in spermatogenesis, not the primitive stem cell. Primary spermatocyte is the immediate progeny of spermatogonium following differentiation.
Two days before the onset of menstruation, secretions of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) reach their lowest levels. What is the cause of this low level of secretion?
- A. The anterior pituitary gland becomes unresponsive to the stimulatory effect of gonadotropin-releasing hormone (GnRH)
- B. Estrogen from the developing follicles exerts a feedback inhibition on the hypothalamus
- C. The rise in body temperature inhibits hypothalamic release of GnRH
- D. Secretion of estrogen, progesterone, and inhibin by the corpus luteum suppresses hypothalamic secretion of GnRH and pituitary secretion of FSH
Correct Answer: D
Rationale: The correct answer is D because two days before menstruation, the corpus luteum secretes estrogen, progesterone, and inhibin, which collectively suppress the hypothalamus's secretion of GnRH and the pituitary gland's secretion of FSH and LH. This hormonal feedback loop helps prepare the body for menstruation.
A: The anterior pituitary gland becoming unresponsive to GnRH does not explain the low FSH and LH levels.
B: Estrogen from developing follicles typically exerts a positive feedback on the hypothalamus, not inhibitory feedback.
C: The rise in body temperature does not directly impact FSH and LH levels; it is more related to ovulation.