Nokea
Which of the following is responsible for secondary sex characteristics in females?
- A. Estrogens
- B. Progesterone
- C. Follicl
- D. stimulating hormone (FSH)
Correct Answer: A
Rationale: Estrogens are responsible for secondary sex characteristics in females as they promote breast development, regulate the menstrual cycle, and contribute to the distribution of body fat. Progesterone mainly prepares the uterus for pregnancy. Follicle-stimulating hormone (FSH) plays a role in the development of ovarian follicles and the maturation of eggs but does not directly influence female secondary sex characteristics.
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Which questions are appropriate for a symptom analysis of a patient with benign prostatic hyperplasia?
- A. How often have you found that you stopped and started again several times when you urinated?
- B. How often have you had to urinate again less than 2 hours after you finished urinating?
- C. How often have you been incontinent of urine?
- D. How often have you had constipation due to the enlarged prostate?
Correct Answer: B
Rationale: The correct answer is B because frequent urination less than 2 hours after finishing can be indicative of benign prostatic hyperplasia (BPH). This symptom, known as urgency, is common in patients with BPH due to bladder irritation. Option A relates more to urinary flow patterns, not specifically associated with BPH. Option C pertains to urinary incontinence, which is not typically a symptom of BPH. Option D is not directly related to BPH symptoms, as constipation is not a common manifestation of this condition.
A scientist studying developmental physiology performs an experiment in which a substance is given to pregnant rats that give birth to pups that have XY chromosomes but female genital organs. What was the substance given to the rats?
- A. An antibody that blocked the effect of human chorionic gonadotropin in the embryo and fetus
- B. A large quantity of estrogen-like compounds
- C. Follicle-stimulating hormone
- D. Testosterone
Correct Answer: A
Rationale: The correct answer is A: An antibody that blocked the effect of human chorionic gonadotropin in the embryo and fetus. Human chorionic gonadotropin (hCG) is crucial for male sexual differentiation. Blocking its effects would lead to the development of female genital organs in pups with XY chromosomes. Estrogen-like compounds (B) and follicle-stimulating hormone (C) are not directly involved in male sexual differentiation. Testosterone (D) is responsible for male sexual development, so giving testosterone would not result in female genital organs in XY pups.
A newborn infant obtains maternal antibodies from the mother's
- A. laguno.
- B. colostrum.
- C. rubell
- D. placent
Correct Answer: B
Rationale: The correct answer is B: colostrum. Colostrum is the first milk produced by the mother after giving birth. It is rich in antibodies, providing passive immunity to the newborn. This helps protect the infant from infections until its own immune system fully develops.
A: laguno - Not a substance related to maternal antibodies.
C: rubell - Incorrect spelling and not relevant to maternal antibodies.
D: placent - While the placenta does provide nutrients and oxygen to the fetus, it is not the source of maternal antibodies transferred to the newborn.
Seven days after ovulation, pituitary secretion of luteinizing hormone (LH) decreases rapidly. What is the cause of this decrease in 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 and progesterone by the corpus luteum suppresses hypothalamic secretion of GnRH and pituitary secretion of LH
Correct Answer: D
Rationale: Step 1: After ovulation, the follicle transforms into the corpus luteum.
Step 2: The corpus luteum secretes estrogen and progesterone.
Step 3: Estrogen and progesterone exert negative feedback on the hypothalamus.
Step 4: This inhibits the secretion of GnRH from the hypothalamus.
Step 5: Decreased GnRH leads to reduced LH secretion from the pituitary.
Therefore, the correct answer is D because the secretion of estrogen and progesterone by the corpus luteum suppresses the hypothalamic secretion of GnRH, resulting in decreased pituitary LH secretion.
Summary:
A: Incorrect. The anterior pituitary gland's responsiveness to GnRH is not the cause of the decrease in LH secretion.
B: Incorrect. Estrogen exerts negative feedback on the hypothalamus, not the pituitary.
C: Incorrect. Rise in body temperature does not directly inhibit GnRH secretion
Sella turcica is a __________ in the sphenoid bone in which
- B. Groove
- C. Projection
- D. Depression
Correct Answer: D
Rationale: The correct answer is D: Depression. Sella turcica is a saddle-shaped depression in the sphenoid bone that houses the pituitary gland. It is not a groove (B) as it is a deeper concavity. It is not a projection (C) as it is a recessed area rather than a raised structure. It is not a foramen (A) as it is a hollowed-out area rather than a small opening. Therefore, the most accurate description of sella turcica is a depression in the sphenoid bone.