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Lecture 23

Human Reproductive System

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Anatomy of the Male Reproductive System

• Testes– Produce

spermatozoa (gametes)

– Produce androgens (hormones)

• Series of ducts• Accessory glands (3)

– Secretions added to sperm to form semensemen

– Seminal vesicle, prostate gland, and bulbourethral gland

Fig. 28.11

Urinary bladder

Ductusdeferens

Urethra

Penis

GlansPrepuce

Ureters

Seminal vesicle

Ejaculatory duct

Prostate gland

Bulbourethral glandAnus

Epididymis

Testis

Scrotum

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Anatomy of the Male Reproductive System

• Supporting structures– Scrotum

• 2 chambered sac that contains testes

• Muscles help regulate temperature

– Penis• Important sexual

organ and part of the urinary system

Fig. 28.12

Ureter

Urinary bladder

Ductus deferens

Epididymis

Testis

Penis

Spermatic cord

Cremaster muscle

Dartos muscle

Scrotum

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Descent of Testes• Descent

– Pass from abdominal cavity through inguinal canal to scrotum

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Testes• Compartments divided

by septa– Seminiferous tubules

• Empty into efferent ductules

• Efferent ductules empty into epididymis

– Epididymis• Site of sperm cell

maturation• 12-16 days

Fig. 28.13

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Male Reproductive StructuresDucts

• Ductus deferens or vas deferens– Passes from

epididymis into abdominal cavity

• Ejaculatory duct– Joining of ductus

deferens and seminal vesicle

Urinary bladder

Ureter

Seminal vesicle

Ejaculatoryduct

Prostategland

Bulbourethral gland

Urethra

Ductus deferens

Testis

Epididymis

Fig. 28.15

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Male Reproductive StructuresUrethra

• Urethra– Extends from urinary

bladder to distal end of penis

– Passageway for urine and male reproductive fluids

Urinary bladder

Ureter

Seminal vesicle

Ejaculatoryduct

Prostategland

Bulbourethral gland

Urethra

Ductus deferens

Testis

Epididymis

Fig. 28.15

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Male Reproductive StructuresPenis

• Three columns of erectile tissue that engorge with blood– Corpora cavernosa (2)

– Corpus spongiosum (1)

• Glans penis– Prepuce or foreskin

covers• Circumcision: Surgical

removal

Glans

Urinary bladder

Ureter

Urethra

Testis

Corpus cavernosum

Penis

Corpus spongiosum

Fig. 28.15Clinical View, pg. 866

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Anatomy of Female Reproductive System

• Female reproductive organs– Ovaries– Uterine tubes– Uterus– Vagina– External genital

organs– Mammary glands Fig. 28.2

Anus

Uterine tube

Ovary

Uterus

Urinary bladder

Urethra

ClitorisExternal urethral

orificeVaginal orifice

Ureter

Fimbriae of uterine tube

Cervix of uterus

Rectum

Vagina

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Uterine Tubes

• Uterine or fallopian tubes or oviducts– Open directly into

peritoneal cavity to receive oocyte from ovary

– Transport oocyte or zygote from ovary to uterus Fig. 28.3(a) Posterior view

Broad ligament

Uterine tube

Cervix Ureter

UterusFimbriae

Ovary

Infundibulum

Vagina

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Uterus & Vagina

• Uterus– Parts: fundus, body, cervix– Composed of 3 layers

• Perimetrium: Serous membrane • Myometrium: Smooth muscle• Endometrium: Mucous membrane

Fig. 28.7

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Female External Genitalia

• Vulva external female genitalia– Vestibule: Space

• Labia minora: Form borders on sides

• Clitoris: Erectile structure

– Corpora cavernosa

– Corpora spongiosa

Fig. 28.9

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Review Question

The structure of the female reproductive system that is homologous to the penis of the male system is the

(a) Vagina(b) Labia minora(c) Uterus(d) Fallopian tubes(e) Clitoris

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Points to RememberPoints to Remember

• Male and female reproductive systems share similarities as evidence of homology

• Important functions of:– Production of gametes and sex hormones– Production of sperm (temperature-sensitive)– Receiving sperm (semen is mixture of sperm and

secretions of three accessory glands)– Providing site for development of fetus and birth– Breast milk secretions provide nourishment

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Questions?