Matching Hormones with Their Definitions
The correct pairings are: Androgens - B (male sex hormones), Steroid - A (a class of hormone derived from cholesterol), Gonadotropins - C (LH and FSH), and Progesterone - D (secreted by the corpus luteum to sustain the endometrium).
Detailed Explanation of Each Hormone
Androgens - B (Male sex hormones)
Androgens are steroid hormones that function as male sex hormones. They are essential for both sexes, though present in much higher concentrations in males 1. Testosterone is the predominant androgen in males, while in females, testosterone concentrations are approximately 15-fold lower 1. Androgens are responsible for:
- Development of male secondary sex characteristics
- Initiation and maintenance of spermatogenesis
- Mediation of physiological actions through the androgen receptor 2
In males, testosterone is primarily produced in testicular Leydig cells, while in females, androgen precursors are biosynthesized in the adrenal cortex and ovaries and converted into testosterone in peripheral tissues 1.
Steroid - A (A class of hormone derived from cholesterol)
Steroids represent a class of hormones derived from cholesterol. All steroid hormones share a common chemical structure with four interconnected carbon rings. This classification includes:
- Sex hormones (androgens, estrogens, progestins)
- Corticosteroids (glucocorticoids, mineralocorticoids)
- Vitamin D derivatives
The ESPEN guidelines note that anabolic or anabolic-androgenic steroids are derived from cholesterol and mimic male sex hormones, increasing protein synthesis especially in skeletal muscle cells 3.
Gonadotropins - C (LH and FSH)
Gonadotropins refer specifically to luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which are glycoprotein hormones produced and secreted by the anterior pituitary gland. These hormones:
- Regulate gonadal function in both males and females
- Control reproductive processes including gametogenesis and steroidogenesis
- Are essential for fertility and sexual development
In males, gonadotropins contribute to steroid hormone production along the classic Δ4 pathway and co-activate alternative pathways of testosterone biosynthesis 4. Combined oral contraceptives (COCs) prevent ovulation by inhibiting gonadotropin-releasing hormone, which subsequently inhibits follicle-stimulating and luteinizing hormones 3.
Progesterone - D (Secreted by the corpus luteum to sustain the endometrium)
Progesterone is a steroid hormone primarily secreted by the corpus luteum in the ovary following ovulation. Its primary functions include:
- Sustaining the endometrium during the luteal phase of the menstrual cycle
- Preparing the uterus for implantation of a fertilized egg
- Maintaining pregnancy if conception occurs
Micronized bioidentical progesterone has demonstrated efficacy for alleviating PMS-related sleep disturbances through its action on GABA-A receptors in the brain 5. Progesterone receptors are expressed in the vasculature, though their role in cardiovascular disease development remains poorly defined 5.
Clinical Relevance
Understanding these hormones and their functions is essential in clinical practice, particularly for:
- Diagnosing and treating reproductive disorders
- Managing hormone replacement therapies
- Understanding the mechanisms of hormonal contraceptives
- Treating conditions like acne (where COCs with their anti-androgenic properties can be beneficial) 3
The correct identification of these hormones and their functions forms the foundation for understanding endocrine physiology and pathophysiology in clinical medicine.