Reproductive Systems Flashcards
(33 cards)
Structures Overview
1) Gonads (Testes/ Ovaries)
- Produce gametes + hormones
2) Ducts
- Transport + store hormones
3) Accessory Glands
- Produce secretions the support gametes
Gonads = Testes
- Located within the scrotum (skin + CT)
- Surrounded by 2 tunics:
1) Tunica Vaginalis - Outer serous membrane
- Derived from peritoneum
2) Tunica Albuginea - Inner fibrous capsule of CT
- Extends inward to divide testis into lobules
Seminiferous Tubules (In each Lobule)
- Produce sperm by spermatogenesis
- Tubules unite to form rete testis (rete = network)
- Walls contain:
1) Germ cells in various stages of development
2) Sertoli Cells (sustentocytes)
Sertoli cells
Surround developing gametes
- Extend from basement membrane to lumen
- Support and nourish germ cells
- Have tight junctions - form blood- testis barrier - protects sperm from immune system, toxins, drugs etc.
- Produce testicular fluid - for transport of sperm in lumen
- Respond to follicle-stimulating hormone (FSH)
Lydia Cells (Interstital cells) (In each Lobule)
- In CT between seminiferous tubules
- Secrete testosterone (hormone)
Ducts (Male Structure)
- Sperm from seminiferous tubules into rite testis
- Then into duct system:
1) Epididymis
2) Vas (ductus) deferens
3) Ejaculatory Duct
4) Urethra
Epididymis
- Posterior border of testis
- Stores sperm
- Sperm mature (develop ability to swim)
Vas (ductus) Deferens
- Enters pelvic cavity
- Loops over posterior bladder
- Vasectomy = vas deferent cut and tied off
- Spermatic Cord - contains vas deferens, nerves (ANS) veins, artery, lymph vessels, muscle (skeletal)
Ejaculatory Duct
Formed by union of vas deferent and duct from seminal vesicle
Urethra
- 3 Regions:
1) Prostatic - through prostate
2) Membranous - through urogenital diaphragm
3) Penile (spongy) - through corpus spongiosum of penis - Open on the glans penis
Penis
- Parts:
1) Root
2) Body (shaft)
3) Glans penis (enlarged tip) - 3 Bodies of erectile tissue - contains blood sinuses, bound by CT
1) 2 copra cavernosa (dorsal portion of root and shaft)
2) 1 corpus spongiosum (the glans and the mid ventral portion of the root and shaft, surrounding the urethra)
Accessory Glands
~95% of semen
1) Seminal Vesicles (2)
2) Prostate Gland (1)
3) Bulbourethral Glands (2)
Seminal Vesicles
- Posterior to bladder
- Secrete alkaline fluid that contains fructose to nourish the sperm
- ~60% of volume of semen
Prostate Gland
- Inferior to bladder and encircles prostatic urethra
- Secrets milky, alkaline fluid - nourishes sperm
- ~30% of volume of semen
Spermatogenesis
- Sperm production (within seminiferous tubules)
- Differentiation of a spermatid = spermatogenesis:
- Develop acrosome + flagellum
- Lose most cytoplasm
- LOOK UP DIAGRAM
Spermatozoon Structure
1) Head
- Nucleus (23 chromosomes (n))
- At tip of nucleus = acrosome - contains digestive enzymes (to penetrate oocyte)
2) Body (mid-piece)
- Large # mitochondria which produce ATP for movement
3) Tail = flagellum
- Propel sperm
- Made of microtubules
Semen
- Sperm, testicular fluid + accessory gland secretions
- 2-5 mL released at ejaculation - contains 20-150 million sperm/mL
- pH 7.2-7.6
- Provides sperm with transportation medium, nutrients + protection
Gonads = Ovaries
- Located in pelvic cavity on lateral sides of uterus
- Histology:
4 layers:
1) Superficial/ germinal epithelium
2) Tunica albuginea - CT
3) Ovarian Cortex - Contains ovarian follicles + CT
- Follicles = layers of cells surrounding immature egg (support +protect)
4) Ovarian Medulla - Blood + lymph vessels, nerves, CT
Ovaries are held in place by:
1) Ovarian Ligament
- To uterus
2) Suspensory Ligament
- To pelvic wall
3) Mesovarium
- Superior membrane
NOTE: Suspensory ligament + mesovarium = parts of broad ligament = parietal peritoneum
Uterine (Fallopian) Tubes
- 3 Sections:
1) Infundibulum - Suspended over ovary
- Has finger-like projections = fimbriae
2) Ampulla = middle - Fertilization occurs here
3) Isthmus - Connects to uterus
Uterine Tubes Histology
1) Mucosa
- Simple columnar epithelium with cilia or microvilli
- Moves oocyte or cell mass along tube
- Secrets nutrient fluid
2) Muscularis Externa
- Smooth muscle - helps movement
3) Serosa
- Visceral peritoneum
Uterus
- Hollow organ
- 3 parts:
1) Fundus - above level of uterine tubes
2) Body - Main portion
- Space within = uterine cavity
3) Cervix - Inferior, narrow portion - opens into vagina
Uterus held in place by:
- Supportive membranes (attach uterus to abdominal wall)
1) Broad ligaments - peritoneum
2) Round ligaments - Fibrous CT - attach uterus to anterior body wall
3) Uterosacral Ligaments - Peritoneum - attach to sacrum
Uterus Histology
1) Peritmetrum
- Outer layer
- Visceral peritoneum
2) Myometrium
- 3 layers of smooth muscle (muscularis externa)
3) Endometrium
- Mucous membrane
- Contains endometrial glands - secrete a nutritive fluid
- 2 layers:
a) Stratum Functionalis
- Faces uterine cavity
- Shed monthly (menstruation)
b) Stratum Basalis
- Permanent
- Undergoes mitosis to replace funtionalis
