In male individuals, testosterone is normally produced by?

AIIMS BBSR SNO - 2019

Applied Physiology

Easy

Appeared in: AIIMS BBSR SNO - 2019

Explanation

The interstitial cells of Leydig are specialized cells located in the connective tissue (interstitium) between the seminiferous tubules of the testes.
Their primary function is to synthesize and secrete testosterone, the principal male androgen.
This process is regulated by Luteinizing Hormone (LH), which is released from the anterior pituitary gland.
The provided image visually confirms the location of Leydig cells in the interstitial space, separate from the Sertoli cells within the tubules.

Option A: Sertoli cells do not produce testosterone. Their main roles are to provide structural and nutritional support to developing sperm cells (spermatogenesis) and to form the blood-testis barrier.
Option C: The vas deferens is a duct, not a hormone-producing gland. Its function is to transport mature sperm from the epididymis to the ejaculatory duct in preparation for ejaculation.
Option D: The epididymis is a coiled tube attached to the back of the testis where sperm undergo maturation and are stored. It does not produce testosterone.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Physiology of the male reproductive system, specifically the site of testosterone production as background academic context rather than a clinical decision trigger.
Understanding the source of testosterone is fundamental for diagnosing and managing male hypogonadism (low testosterone), which can affect fertility, mood, energy levels, and bone health.
Nurses may be involved in patient education regarding hormone replacement therapy, explaining how it supplements the function of deficient Leydig cells.
What if? If a male patient has a pituitary tumor that underproduces Luteinizing Hormone (LH), the Leydig cells would not be stimulated, leading to secondary hypogonadism. The answer to the question remains the same (Leydig cells produce testosterone), but the cause of the deficiency is in the pituitary, not the testes.

How to Approach the Question

First, identify the key term in the question: 'testosterone production'.
Recall the basic anatomy and physiology of the male reproductive system.
Analyze the provided image, which shows a cross-section of a seminiferous tubule and labels both Sertoli cells (inside the tubule) and Leydig cells (outside the tubule).
Evaluate each option based on your knowledge and the visual aid:
Sertoli cells: Recall their role is supportive ('nurse cells').
Interstitial cells of Leydig: Recall their location in the 'interstitial' space and their endocrine function.

Concept Tested & Keywords

Concept Tested: Physiology of the male reproductive system, specifically the site of testosterone production.
Stem keywords: male individuals, testosterone, produced by
Lead-in keywords: BEST, MOST RELEVANT CLUE
Clinical cues: Age/sex group narrows the expected diagnosis, intervention, or normal reference range.

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