chapter 28 Male Reproductive System

Male Anatomy

1. Testes

2. Duct System

3. Accessory Glands

4. Supporting Structures

Exocrine Function

Sperm Production

Endocrine Function

Testosterone Production

Main Components of Testes

-Tunica Albuginea

-Seminiferous Tubules

-Rete Testis

-Interstitial Cells

Epididymis

Site of sperm maturation

Seminiferous Tubule

Site or sperm production: 1-3 tubes found in lobules

Ductus Deferens (Vas Deferens)

Propel live sperm from their storage sites in the epididymis into the urethra

-vasectomy

Urethra

has both urinary & reproductive system functions in males

3 Regions of Urethra

• Prostatic Urethra (surrounded by prostate)

• Membranous Urethra (from prostatic region to penis)

• Spongey Urethra (running in length of penis)

Seminal Vesicles location

located at base of bladder

Seminal Vesicles Produce Approx…

60% of volume of semen

Seminal Vesicles Secretion Nourishes…

& activates sperm - rich in sugar, vitamin C & prostaglandins

Seminal Vesicles Empties

Into the ductus deferens

Prostate Gland

• encircles the urethra

• secretions activate sperm

Bulbourethral Glands or Cowpers Gland

• Pea sized

• Located inferiority to prostate gland

• Produces mucous that drains the urethra, cleaning out acidic urine

• Active when sexually excited

Scrotum

Protects & regulate temperature of the Testes & holds testes

Scrotum divided into

2 compartments by median septum

Scrotum Functions in

Testicular thermoregulation

(Sperm are not produced at core body temperature)

Semen

Mixture of sperm & accessory gland secretions

• protects sperm

• Liquid provides transport medium

• 2-3 Milliliter Ejaculated

• 50-130 million sperm per milliliter

Penis Delivers

Sperm into the female reproductive tract

Components of Penis

• Shaft

• Glans penis-tip

• Foreskin

• Erectile Tissue

Foreskin

Covers the proximal end of gland (sometimes surgically removed in a procedure called circumcision)

Erectile Tissue

Slinger tissue that fills with blood during sexual excitement

Each day About …. Sperm Complete Spermatogenesis

300 million

Lifespan of Sperm is

48 hours in female reproductive tract

Head of Sperm

Nucleus with 23 chromosomes (haploid or n)

Acrosome

Vesicle filled with oocyte penetrating enzymes

Testosterone Production

Produced by Leydig Cells

Effects of Testosterone

Stimulates spermatogenesis & enlargement sexual organs

• penis, testes, scrotum, ducts, glands & muscle mass enlarge

• hair, scent & sebaceous glands develop

• Stimulates libido