Goals:Identify the structures of the male and female reproductive systems, including the gross and microscopic anatomy of the organs, structures and accessory glands and their basic functions.Explain meiosis, spermatogenesis and oogenesis.Discuss the changes that occur in the female reproductive system during pregnancy.

Gonads, or Primary Sex Organs = ovaries and testesGonads, or Primary Sex Organs = ovaries and testes

Produce gametes (ova and spermatozoa)Produce gametes (ova and spermatozoa)

And hormonesAnd hormones

Transportation SystemTransportation System

Transport of gametesTransport of gametes

Secondary or Accessory OrgansSecondary or Accessory Organs

Glands (e.g., prostate)Glands (e.g., prostate)

External genitaliaExternal genitalia

Primary reproductive organs produce Primary reproductive organs produce gametesgametes

Secondary reproductive organs:Secondary reproductive organs:

Seminal fluidSeminal fluid

Storage of spermatozoaStorage of spermatozoa

Male reproductive and urinary tracts Male reproductive and urinary tracts are partially sharedare partially shared

Function: supports, protects, and regulates Function: supports, protects, and regulates temperature temperature

Scrotum consists ofScrotum consists of

Skin, fasciaSkin, fascia

Dartos muscle (smooth)Dartos muscle (smooth)

Tunica vaginalisTunica vaginalis

Median raphéMedian raphé

Allows the testes to remain ~3°C cooler Allows the testes to remain ~3°C cooler than core temperaturethan core temperature

Involuntary contraction of dartos and Involuntary contraction of dartos and cremaster muscles (cremasteric reflex) in cremaster muscles (cremasteric reflex) in response to cold or sexual arousalresponse to cold or sexual arousal

4 month fetus

Develop adjacent to kidneysDevelop adjacent to kidneys

Descend into scrotum Descend into scrotum through through inguinal canal inguinal canal (function of (function of gubernaculum gubernaculum testistestis) before birth) before birth

Blood Supply viaBlood Supply via gonadal gonadal arteriesarteries

Parietal peritoneum is Parietal peritoneum is carried along carried along lining of lining of scrotumscrotum

Spermatic cord: Spermatic cord: bundle bundle containing all the “duct containing all the “duct work”work”

Widening of inguinal Widening of inguinal canalcanal

Usually due to injury or Usually due to injury or heavy liftingheavy lifting

Sometimes scrotal Sometimes scrotal herniahernia

Strangulation of Strangulation of intestine is possibleintestine is possible

In 3% of full-term and 30% of premature deliveries

Significance? - Treatment?

Fibrous capsule – Fibrous capsule – tunica tunica albugineaalbuginea – surrounds testes – surrounds testes

Lobules contain approx. 800 Lobules contain approx. 800 Seminiferous TubulesSeminiferous Tubules collect collect at at rete testisrete testis

Interstitial (Leydig)Interstitial (Leydig) Cells Cells make testosteronemake testosterone

Sustentacular (Sertoli)Sustentacular (Sertoli) cells cells aid spermatogenesisaid spermatogenesis

SeminiferousSeminiferousTubulesTubules

Sertoli Cells:Sertoli Cells: Maintenance of blood testis barrierMaintenance of blood testis barrier

special lumen fluid high in sex hormones, Kspecial lumen fluid high in sex hormones, K++ and aa and aa Protection from immune attack (due to sperm specific Protection from immune attack (due to sperm specific

Ag)Ag)

Suspend spermatids and support Suspend spermatids and support spermatogenesis and spermiogenesisspermatogenesis and spermiogenesis FSH and Testosterone work via Sertoli cells FSH and Testosterone work via Sertoli cells Secretion of inhibin to slow sperm productionSecretion of inhibin to slow sperm production Secretion of androgen-binding protein (ABP)Secretion of androgen-binding protein (ABP)

SpermatogoniaSpermatogonia divide (mitosis) and one of the divide (mitosis) and one of the daughter cells matures into a daughter cells matures into a primary (1°) primary (1°) spermatocytespermatocyte..

Meiosis begins, two Meiosis begins, two secondary (2°) secondary (2°) spermatocytesspermatocytes. Another division produces . Another division produces spermatidsspermatids..

Crossing over (not in book)Crossing over (not in book)

Spermiogenesis:: Spermatid maturation into Spermatid maturation into spermatozoa with help of spermatozoa with help of sustentacular (Sertoli) sustentacular (Sertoli) cellscells

SpermiationSpermiation:: Spermatozoon released into lumen Spermatozoon released into lumen of seminiferous tubulesof seminiferous tubules

Fig 24.4Fig 24.4

Spermatid maturation into spermatozoa with help of sustentacular (Sertoli) cells

Spermiation: Spermatozoon released into lumen of seminiferous tubules

Interstitial CellsInterstitial Cells Located between tubules produce Located between tubules produce

testosteronetestosterone Controlled by LHControlled by LH

Testosterone, like other Testosterone, like other hormones, is secreted into the hormones, is secreted into the bloodstreambloodstream

Mature sperm has 3 portions:Mature sperm has 3 portions:

1.1. Head with acrosome (containing Head with acrosome (containing enzymes) and compressed enzymes) and compressed nucleus nucleus

1.1. Acrosomal ReactionAcrosomal Reaction

2.2. Middle piece with lots of Middle piece with lots of mitochondria. Why?mitochondria. Why?

3.3. Tail - flagellum Tail - flagellum - (rotates in - (rotates in corkscrew fashion)corkscrew fashion)

~ 7 m long, single tube~ 7 m long, single tube

HeadHead - superior, receives spermatozoa - superior, receives spermatozoa

BodyBody - distal and inferior - distal and inferior

TailTail - leads to ductus deferens - leads to ductus deferens

Functions:Functions:

1) Monitors and adjusts tubular fluid 1) Monitors and adjusts tubular fluid (lining has (lining has stereocilia!)stereocilia!)

2) Recycles damaged spermatozoa2) Recycles damaged spermatozoa

3) Stores sperm and facilitates maturation 3) Stores sperm and facilitates maturation (capacitation)(capacitation)

Rete testis and Efferent ductules

Fig 24.7

Can be palpated as it Can be palpated as it passes over the pubic brim. passes over the pubic brim.

Constituents :Constituents :

Pampiniform plexus of Pampiniform plexus of spermatic veinspermatic vein

Spermatic arterySpermatic artery

Ductus (vas) deferensDuctus (vas) deferens

Smooth muscle Smooth muscle

LymphaticsLymphatics

Nerves-ilioinguinal and Nerves-ilioinguinal and genitofemoralgenitofemoral

Local anestheticLocal anesthetic Remove a small section Remove a small section

of each vas deferensof each vas deferens Seminal fluid is Seminal fluid is

unchangedunchanged Spermatozoa are Spermatozoa are

reabsorbedreabsorbed Reversal?Reversal?

Provide for 95% of the seminal fluidProvide for 95% of the seminal fluid 1.1. Seminal VesiclesSeminal Vesicles

2.2. Prostate GlandProstate Gland

3.3. Bulbourethral glandsBulbourethral glands

Posterior view

Paired, posterior to urinary Paired, posterior to urinary bladderbladder

Tubular Tubular (~ 15 cm)(~ 15 cm)

Produce 60% of seminal Produce 60% of seminal fluid, hormones, fructose, fluid, hormones, fructose, etc.etc.

Activate sperm (leading to Activate sperm (leading to motility)motility)

20 - 30% of seminal fluid 20 - 30% of seminal fluid

Single, doughnut-shapedSingle, doughnut-shaped

Left and right lobesLeft and right lobes

Prostatic urethraProstatic urethra

Secretion contains:Secretion contains: Citrate Citrate Seminal plasmin (mild antibiotic)Seminal plasmin (mild antibiotic)

Risk Factors:Risk Factors: AgeAge RaceRace GeneticsGenetics

Usually grows slowlyUsually grows slowly Often slow urination is first signOften slow urination is first sign Digital Rectal Exam (DRE) and/or Digital Rectal Exam (DRE) and/or

PSA, then more sophisticated tests PSA, then more sophisticated tests such as CT or MRIsuch as CT or MRI

Treatment depends on size of tumor Treatment depends on size of tumor and other factorsand other factors

Pea size, paired, at base of Pea size, paired, at base of penispenis

Produce about 10% of semenProduce about 10% of semen

Alkaline mucus buffers the acid Alkaline mucus buffers the acid that may be present in urinethat may be present in urine

2-5 ml ejaculate2-5 ml ejaculate

Ejaculation of semen by pelvic floor Ejaculation of semen by pelvic floor and penile muscles (Sympathetic and penile muscles (Sympathetic division induces peristalsis in division induces peristalsis in tract)tract)

Constituents:Constituents:1. sperm - 20 - 100 million 1. sperm - 20 - 100 million

sperm / mlsperm / ml2. seminal fluid – 60% 2. seminal fluid – 60%

from seminal vesiclesfrom seminal vesicles3. enzymes - proteases 3. enzymes - proteases

and seminal plasminand seminal plasmin

RootRoot - fixed to ischial rami - fixed to ischial rami

GlansGlans – enlargement of corpus – enlargement of corpus spongiosumspongiosum PrepucePrepuce = foreskin – partially covers = foreskin – partially covers

glans and surrounds external urethral glans and surrounds external urethral meatus (removed in meatus (removed in circumcision))

Preputial glands - produce smegma Preputial glands - produce smegma (supports bacterial growth, such as (supports bacterial growth, such as E. E. colicoli))

Fig 27.9

circumcision

•ShaftShaft with erectile tissues with erectile tissues

•Corpus Cavernosum (2)Corpus Cavernosum (2)

•Corpus Spongiosum Corpus Spongiosum (surrounds urethra)(surrounds urethra)

•Dorsal Artery and VeinDorsal Artery and Vein

•Penile UrethraPenile Urethra

Video of male anatomy

Seminiferous tubulesSeminiferous tubules Convoluted, then StraightConvoluted, then Straight

Rete testisRete testis Efferent DuctulesEfferent Ductules Epididymis (head, body, tail)Epididymis (head, body, tail) Vas (ductus) deferensVas (ductus) deferens Ampulla of vas deferensAmpulla of vas deferens Ejaculatory ductEjaculatory duct Prostatic urethraProstatic urethra Membranous urethraMembranous urethra Penile (spongy) urethraPenile (spongy) urethra

Fig 27.8

Posterior Posterior view!view!

Vas deferensVas deferens