Ch 27: Reproductive System

1
Ch 27 Reproductive System

• 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.

http//hastaneciyiz.blogspot.com
Medical ppt
2
General Organization

• Gonads ? gametes hormones
• Ducts ? transport of . . . ?
• Glands ? secrete fluid
• Perineal structures external genitalia

3
Male Reproductive Anatomy

• Primary reproductive organs produce gametes
• Secondary reproductive organs . . .
• Male reproductive and urinary tracts are
  partially shared

Fig 27-1
4
Testes (paired glands)
4 month

• Develop adjacent to kidneys
• Descend into scrotum through inguinal canal
  (function of gubernaculum testis)
• Peritoneal lining is carried along ? lining of
  scrotum
• Spermatic cord bundle containing all the duct
  work
• Cryptorchidism

Figs 27-2/3
5
Cryptorchidism

• In 3 of full-term and 30 of premature
  deliveries
• Significance? - Treatment?

6
Spermatic Cord
Can be palpated as it passes over the pubic
brim. Constituents 1. Pampiniform plexus of
spermatic vein 2. Spermatic artery 3.
Ductus (vas) deferens 4. Lymphatics 5.
Nerves-ilioinguinal and genitofemoral
Fig 27.3
7
Scrotum

• Function supports and protects testes
• Structure Skin underlying superficial
  fascia
• Dartos muscle in dermis
• Cremaster muscle - continuous with abdominal
  wall muscles (?)
• Involuntary contraction (cremasteric reflex) in
  response to ________
• Scrotal sac forms 2 separate chambers

8
Structure of Testes

• Fibrous capsule tunica albuginea
  surrounds testes
• Scrotal cavity lined by tunica vaginalis
  parietal and visceral layers
• 200-300 lobules
• 3 seminiferous tubules

Figs 27-4/5
9
From Spermatocyte to Spermatozoon

• Spermatogenesis Meiosis of primary spermatocytes
  ? spermatids
• Spermiogenesis Spermatid maturation into
  spermatozoa within Sertoli cells
• Spermiation Spermatozoon released into lumen

10
Sustentacular (Sertoli) Cells

• Maintenance of blood testis barrier
• special lumen fluid high in sex hormones, K and
  aa
• protection from immune attack (due to sperm
  specific ag)
• Suspend spermatids and support spermatogenesis
  and spermiogenesis
• ? FSH and Testosterone work via Sertoli cells
• Secretion of inhibin to slow sperm production
• Secretion of androgen-binding protein (ABP)

11
Anatomy of a Spermatozoon

• Mature sperm has 3 portions
• Head with acrosome (containing _______ )
• Middle piece with nucleus and lots of ?
• Tail - flagellum - (rotating in corkscrew fashion)

See fig 27-6
12
Epididymis

• 7 m long
• Head - superior, receives spermatozoa
• Body - distal and inferior
• Tail - leads to ductus deferens
• Functions
• 1) Monitors and adjusts tubular fluid
  (stereocilia!)
• 2) Recycles damaged spermatozoa
• 3) Stores sperm and facilitates maturation

Rete testis and Efferent ductules
13
Pathway of Sperm

• Seminiferous tubules
• Rete testis
• Epididymis
• Vas (ductus) deferens
• Ampulla of vas deferens
• Ejaculatory duct
• Prostatic urethra
• Membranous urethra
• Penile (spongy) urethra

Fig 27.8
14
Accessory Glands

• Provide for 95 of the seminal fluid
• 1) Seminal Vesicles
• Paired, on back wall of urinary bladder
• Tubular ( 15 cm)
• Produce 60 of semen, hormones, fructose, etc.
• Activate sperm (leading to motility)

Fig. 27.8
15
Prostate Gland

• 20 - 30 of seminal fluid
• Single, doughnut-shaped
• Secretion contains
• Citrate
• Seminal plasmin (mild antibiotic)
• Prostate specific antigen (PSA) blood test for ?

16
Bulbourethral glands (Cowpers glands)

• Pea size, paired, at base of penis
• Produce about 10 of semen
• Alkaline mucus - function??

17
Semen

• 2-5 ml ejaculate
• Ejaculation of semen by pelvic floor and penile
  muscles (Sympathetic division induces peristalsis
  in tract)
• Constituents
• 1. sperm - 20 - 100 million sperm/ ml
• 2. seminal fluid - see above glands
• 3. enzymes - proteases and seminalplasmin

18
Penis

• Root - fixed to ischial ramus
• Body with erectile tissues
• Glans enlargement of corpus spongiosum
• Prepuce - foreskin partially covers glans and
  surrounds external urethral meatus (may be
  removed in circumcision)
• Preputial glands - produce smegma (supports
  bacterial growth, such as E. coli)

Fig 27.9
The End
19
Medical ppt
http//hastaneciyiz.blogspot.com