Study sheet: Male Reproductive Ducts and Glands

📋 Course Outline

1. Epididymis Structure and Function
2. Vas Deferens and Ejaculatory Duct
3. Urethral Pathways
4. Accessory Glands Overview
5. Prostate Gland Secretions
6. Seminal Vesicle Functions
7. Bulbourethral Glands
8. Penis and External Genitalia

📖 1. Epididymis Structure and Function

🔑 Key Concepts & Definitions

• Epididymis : a highly convoluted tube resting on and beside the testis that is about 6 metres long when fully uncoiled

★ Must-know

• The three parts are:

  • the head, or caput epididymis
  • the body, or corpus epididymis
  • the tail, or cauda epididymis

• During passage through the epididymis, sperm mature, become motile and physiologically active, and are then temporarily stored in the tail before entering the vas deferens.

Further detail

• The head of the epididymis receives sperm from the rete testis through the vasa efferentia, the body allows sperm to pass onward, and the tail stores sperm before they enter the vas deferens.

💡 Memory Hook

Head → body → tail: maturation, passage, storage

📖 2. Vas Deferens and Ejaculatory Duct

🔑 Key Concepts & Definitions

• Vas deferens : a partially coiled, thick muscular tube that conducts sperm from each epididymis toward the base of the urinary bladder

★ Must-know

• Each vas deferens joins the duct of a seminal vesicle at the base of the urinary bladder to form an ejaculatory duct about 2 centimetres long, which opens into the prostatic urethra.

Further detail

• There are two vas deferens, one from each epididymis.

💡 Memory Hook

Epididymis → vas deferens → ejaculatory duct → urethra

📖 3. Urethral Pathways

🔑 Key Concepts & Definitions

• Urethra : a 20-centimetre-long tube that provides a common pathway for urine and semen in males

📝 Essential Points

• The urethral regions are: the prostatic urethra, which carries urine, the membranous urethra, which carries urine and semen, the penile urethra, which passes through the penis and opens through the urethral meatus

💡 Memory Hook

Male urethra carries urine and semen; female openings are separate

📖 4. Accessory Glands Overview

📝 Essential Points

• The accessory glands comprise:
  • one prostate gland
  • two seminal vesicles
  • two bulbourethral glands

💡 Memory Hook

P-S-B: prostate, seminal vesicles, bulbourethral glands

📖 5. Prostate Gland Secretions

🔑 Key Concepts & Definitions

• Prostate gland : lies below the urinary bladder and consists of 30 to 50 compound tubulo-alveolar glands embedded in fibromuscular tissue

★ Must-know

• Prostatic secretion forms 30% of semen and is a thin, slightly alkaline, opalescent fluid that counteracts acidity in the vas deferens and vagina.

Further detail

• The secretion contains:
  • acid phosphatase, amylase and protease
  • lipids
  • a small amount of citric acid
  • bicarbonate

📌 Prostatic secretion nourishes sperm and increases their motility, while enlargement of the prostate in older persons compresses the urethra and causes urine retention.

💡 Memory Hook

Alkaline, enzyme-rich secretion → sperm nourishment and increased motility

📖 6. Seminal Vesicle Functions

🔑 Key Concepts & Definitions

• Seminal vesicle : a sac-like mass that is actually a convoluted tube whose duct joins the vas deferens to form a common ejaculatory duct

📝 Essential Points

📌 Seminal-vesicle secretion forms 60% of semen and is expelled during ejaculation by contraction of the vesicle's smooth muscle.

• The secretion contains:
  • citrate
  • fructose
  • hyaluronidase
  • prostaglandins

💡 Memory Hook

Fructose supplies energy, while prostaglandins aid sperm movement

📖 7. Bulbourethral Glands

🔑 Key Concepts & Definitions

• Bulbourethral glands : a pair of yellow, pea-sized glands attached to the urethra below the prostate, with ducts joining the proximal urethra

📝 Essential Points

📌 Before ejaculation, the bulbourethral glands secrete a clear, alkaline, viscous mucus that lubricates the urethra and removes lingering acidic urine that could damage sperm.

💡 Memory Hook

Alkaline mucus → urethral lubrication and acid neutralization

📖 8. Penis and External Genitalia

🔑 Key Concepts & Definitions

• Penis : the male external genital organ located just in front of the scrotum and serves as a passage for both semen and urine

📝 Essential Points

📌 The penis transfers sperm to the female reproductive tract and becomes rigid and erect when blood fills its vascular spaces within erectile tissue.

💡 Memory Hook

A cylindrical erectile organ positioned in front of the scrotum

📊 Synthesis Tables

Male Reproductive Ducts

Structure	Main role	Key connection
Epididymis	Sperm maturation, motility and temporary storage	Continues with the vas deferens
Vas deferens	Conducts sperm	Joins the seminal-vesicle duct
Ejaculatory duct	Carries the combined duct contents	Opens into the prostatic urethra
Urethra	Common passage for urine and semen	Opens externally through the urethral meatus