Nokea
The main structures in erectile tissue responsible for maintaining an erection are the:
- A. pacinian corpuscles
- B. peripheral nerves
- C. helicine arteries
- D. Acrosome phase
Correct Answer: C
Rationale: The correct answer is C: helicine arteries. Helicine arteries are the main structures in erectile tissue responsible for maintaining an erection. They dilate in response to signals from the nervous system, allowing increased blood flow into the penis, leading to an erection. Pacinian corpuscles (A) are sensory receptors for touch and pressure, not involved in erectile function. Peripheral nerves (B) transmit signals between the brain and the penis but are not directly responsible for maintaining an erection. Acrosome phase (D) is a term related to sperm structure and not relevant to erectile tissue function.
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When a nurse is educating a group of women about the risks of breast cancer, she includes which of the following common risk factor?
- A. Older than 30 years of age
- B. Family history of breast cancer
- C. African-American heritage
- D. Breast tenderness, without any sensation
Correct Answer: B
Rationale: Family history is a well-established risk factor for breast cancer.
How many fused parts form sacrum?
- A. 4
- B. 5
- C. 6
- D. 3
Correct Answer: A
Rationale: The sacrum is formed by the fusion of 5 originally separate sacral vertebrae. However, the coccyx is the result of the fusion of 4 originally separate coccygeal vertebrae. Therefore, the sacrum itself is formed by the fusion of 4 parts, making choice A correct. Choices B, C, and D are incorrect as they do not accurately reflect the anatomical structure of the sacrum.
Regarding gross anatomy of male reproductive system
- A. Dartos muscle is responsible to raise and lower the testes
- B. Ductus deferens penetrate the prostate gland to connect with prostatic urethra
- C. Anterior lobe of prostate gland is the main glandular tissue
- D. Buck's fascia encloses body of penis
Correct Answer: B
Rationale: The correct answer is B because the ductus deferens penetrates the prostate gland to connect with the prostatic urethra, forming the ejaculatory duct. This allows for the transport of sperm from the epididymis to the urethra during ejaculation.
A: Dartos muscle is responsible for wrinkling the scrotal skin but not raising and lowering the testes.
C: The anterior lobe of the prostate gland mainly consists of fibromuscular tissue, not glandular tissue.
D: Buck's fascia surrounds the corpora cavernosa and the corpus spongiosum of the penis, not the body of the penis itself.
What factor will inhibit LH secretion?
- A. FSH
- B. progesterone
- C. estrogen
- D. LH
Correct Answer: B
Rationale: The correct answer is B: progesterone. Progesterone inhibits LH secretion by exerting negative feedback on the hypothalamus and pituitary gland. This hormone signals that the body has enough progesterone and does not need additional LH for ovulation. FSH (choice A) stimulates LH secretion, estrogen (choice C) typically increases LH secretion during the menstrual cycle, and LH (choice D) does not inhibit its own secretion.
A man who has been exposed to high levels of gamma radiation is sterile due to destruction of the germinal epithelium of the seminiferous tubules, although he has normal levels of testosterone. Which of the following would be found in this patient?
- A. Normal secretory pattern of gonadotropin-releasing hormone
- B. Normal levels of inhibin
- C. Suppressed levels of follicle-stimulating hormone
- D. Absence of Leydig cells
Correct Answer: A
Rationale: Step 1: High levels of gamma radiation cause destruction of germinal epithelium, leading to infertility.
Step 2: Normal testosterone levels indicate intact Leydig cells, responsible for testosterone production.
Step 3: Normal secretory pattern of gonadotropin-releasing hormone (GnRH) is expected as it regulates pituitary hormone secretion.
Step 4: Inhibin is produced by Sertoli cells (part of germinal epithelium) and would be decreased due to destruction.
Step 5: Follicle-stimulating hormone (FSH) levels would be elevated, not suppressed, due to lack of inhibin feedback.
Step 6: Leydig cells are intact, so Leydig cells are not absent in this scenario.