A nurse is reviewing the components of semen analysis with a client. The nurse explains that the seminal vesicles contribute a significant amount of fluid to semen, which contains fructose. What is the primary purpose of fructose in semen?
To stimulate smooth muscle contractions in the female reproductive tract.
To provide energy for sperm motility.
To act as an antibiotic to prevent urinary tract infections.
To aid in the coagulation of semen after ejaculation.
The Correct Answer is B
Sperm maturation occurs in the epididymis, a highly coiled duct located along the posterior aspect of each testis. Spermatozoa produced in the seminiferous tubules are non-motile and incapable of fertilization until they pass through the epididymis, where they undergo biochemical and structural changes over a period of approximately 12 to 21 days. Mature sperm gain progressive motility and fertilizing capacity. Normal sperm motility should be ≥40%, and normal transit time through the epididymis ranges between 2 to 14 days, depending on frequency of ejaculation.
Rationale for correct answers
B. The epididymis is the primary site for sperm maturation and acquisition of motility. Immature sperm enter the head of the epididymis from the rete testis and progressively mature as they transit through the body and tail. This process is critical for sperm to acquire the ability to swim and fertilize an ovum.
Rationale for incorrect answers
A. The vas deferens functions as a transport conduit, carrying mature sperm from the epididymis to the ejaculatory ducts. It does not contribute to sperm maturation or motility development but is crucial during ejaculation.
C. The seminal vesicles secrete fructose-rich fluid contributing to semen volume and energy supply but do not play a role in sperm storage or maturation. Their function is exocrine, contributing fluid post-sperm maturation.
D. The ejaculatory ducts are short ducts formed by the union of the vas deferens and seminal vesicles. They pass through the prostate and open into the urethra. Their role is purely conductive, with no involvement in sperm development or motility acquisition.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is ["B","D","E"]
Explanation
Sertoli cell function is central to spermatogenesis and testicular immune privilege. Located within seminiferous tubules, Sertoli cells regulate the development and protection of germ cells, form the blood-testis barrier, and secrete regulatory proteins. They produce inhibin, which inhibits follicle-stimulating hormone (FSH), and express androgen-binding protein to maintain high testosterone concentration locally. Serum FSH normal range is A.5–1B.4 mIU/mL in males, and inhibin B normally ranges between 80–400 pg/mL. Sertoli cells do not produce testosterone; Leydig cells do.
Rationale for correct answers
B. Sertoli cells form the blood-testis barrier using tight junctions. This barrier prevents autoimmune reactions by isolating developing sperm from systemic circulation and shields them from harmful substances.
D. Sertoli cells provide metabolic support, secrete nutrients, and phagocytose residual cytoplasm from developing spermatids. They also maintain a controlled environment for germ cell differentiation.
E. Sertoli cells secrete inhibin B in response to FSH stimulation. Inhibin provides negative feedback to the anterior pituitary to regulate FSH secretion and thus maintain spermatogenic homeostasis.
Rationale for incorrect answers
A. Testosterone is not secreted by Sertoli cells. It is synthesized by Leydig cells located in the interstitial tissue of the testes in response to luteinizing hormone (LH). Normal serum testosterone in males is 300–1,000 ng/dL.
C. Sertoli cells do not produce spermatozoa. They facilitate and support spermatogenesis, but spermatozoa are derived from spermatogonia through mitotic and meiotic divisions involving primary and secondary spermatocytes and spermatids.
Take home points
- Sertoli cells form the blood-testis barrier via tight junctions.
- They secrete inhibin, which negatively regulates FSH release.
- They nourish and support germ cell maturation but do not form sperm.
- Testosterone is produced by Leydig cells, not Sertoli cells.
Correct Answer is ["A","B","D"]
Explanation
Testosterone physiology in males plays a vital role in reproductive, musculoskeletal, and behavioral functions. It is primarily synthesized by Leydig cells in the testes in response to luteinizing hormone (LH). Testosterone stimulates spermatogenesis, supports muscle and bone growth, and maintains sexual behavior. Normal serum testosterone levels range between 300–1,000 ng/dL. It exerts negative feedback on the hypothalamic-pituitary-gonadal axis by reducing gonadotropin-releasing hormone (GnRH) and luteinizing hormone, but inhibin, not testosterone, primarily suppresses follicle-stimulating hormone (FSH).
Rationale for correct answers
A. Testosterone stimulates spermatogenesis indirectly by acting on Sertoli cells, which express androgen receptors. It maintains the integrity of the seminiferous epithelium and supports germ cell development.
B. Testosterone promotes anabolic effects, increasing skeletal muscle mass and bone density by stimulating osteoblast activity and muscle protein synthesis. These effects are critical during puberty and for adult male maintenance.
D. Testosterone plays a central role in regulating libido and sexual arousal in males. Low testosterone is associated with decreased sexual desire and erectile dysfunction.
Rationale for incorrect answers
C. Testosterone exerts negative feedback on the hypothalamus, suppressing GnRH secretion. Elevated testosterone levels reduce GnRH, LH, and FSH to maintain homeostasis within the hypothalamic-pituitary-gonadal axis.
E. Testosterone does not directly inhibit FSH. FSH is primarily inhibited by inhibin B, which is secreted by Sertoli cells. Testosterone mainly inhibits LH release by acting on the anterior pituitary and GnRH neurons.
Take home points
- Testosterone supports spermatogenesis through Sertoli cell stimulation.
- It promotes muscle mass and bone growth via anabolic effects.
- It is essential for maintaining male libido and sexual behavior.
- Testosterone inhibits GnRH and LH, not FSH, which is suppressed by inhibin.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.