Generalities & Testes Flashcards
2 Categories of Sex Organs
* Differenciate them
1. Primary Sex Organs – produce sex cells and secrete hormones
2. Accessory Organs – nourish and transports gametes (Glands & Ducts)
Male sex cells
* produced by the __
Spermatocytes
* Testes
Female sex cells
* produced by the __
Oocytes
* Ovaries
Pathway of spermatocytes
Testes => Epididymis => Ductus Deferens => Ejaculatory Ducts => Urethra
Embryological origin of the Testes
* reason for its relocation
Posterior Abdominal Wall (L1 or L2)
* Internal Body temp of 37dc is too high => Superficial Location is 3dc cooler
sac of skin and superficial fascia that encloses the testes
Scrotum
Muscle Responsible for wrinkling scrotal skin
* Trigger:
* Importance:
Dartos muscle
* Trigger: Cold Temperatures
* Importance: It increases thickness and reduces heatloss
Muscle that elevates the Testes
* Trigger:
* Importance:
Cremaster muscle
* Trigger: Cold Temperature
* Importance: Elevates the testes toward the body wall to warm it
Muscle involved in relaxing or descending the Testes
* Trigger
* Importance
Cremaster muscle
* Trigger: Hot Temperature
* Importance: Testes hang low away from body to increase surface area for cooling
What happens to scrotal skin during hot temperatures
It becomes flaccid and loose to promote heatloss
A serous sac that partially encloses the Testes
* Embryological connection
Tunica Vaginalis
* it is an outpocketing of the abdominal peritoneal cavity that precedes the descent of the testes
Composition of the Tunica Vaginalis
- Parietal Layer
- Intermediate Layer
- Visceral Layer
cavity of the Tunica Vaginalis that contains serous fluid and a remnant of the peritoneum
Intermediate Cavity
Why do the connection of Tunica Vaginalis to the peritoneum needs to be destroyed?
To prevent intra abdominal contents from descending to the scrotum
Fibrous capsule of the Testes that has septal extensions
* Function
**Tunica Albuginea **
* Uas septal extensions that project inward to divide the testes into 250 - 300 Lobules
Tubules that are contained within each Lobule
* Function
* Converges posteriorly to form __ that —
Seminiferous Tubules (1 -4)
* sperm production
* Forms the Straight Tubules that conveys the sperm to the Rete Testis
Structure that lies in the mediastinum testis , where the sperm leaves the testes via the Efferent Ductules to enter the Epididymis
Rete Testis
Trace the pathway of sperm from the testes to the epididymis
Seminiferous T => Straight T => Rete Testis => Efferent Ductules => Epididymis
Scrotal Skin is derived from
Abdominal/Perineal Skin
Dartos muscle is derived from
Superficial Fascia => Colle’s Fascia
External Spermatic Fascia is derived from
External Oblique Aponeurosis
Cremastic Fascia and Muscle is derived from
Internal Oblique Muscle
Internal spermatic fascia is derived from
Transversalis Fascia
Tunica Vaginalis is derived from the
Peritoneum
Main Blood Supply of the Testes
* branch of
Testicular (Gonadal a)
* Branch of abdominal aorta @ L2
Main Venous Drainage of the Testes
* Drains to
* Importance of this plexus
Pampiniform Plexus
* Drains to the Testicular vein
* It absorbs heat from the blood before it enters the testes = cool it down [Countercurrent Heat Exchange]
Nerve supply of the Testes
PSNS & SNS; Visceral Sensory nerve fibers
Cells that are in the process of spermatogenesis
* when does sermatogenesis start?
* What stimulates these cells
Spermatogenic Cells
* Starts @ Puberty
* Stimulated by FSH (Ant P)
Stem Cell of sperm
* Process of differentiation of sperm
Spermatogonia => Primary Spermatocytes => Secondary Spermatocytes => Spermatids = Sperm
Cells surrounding the spermatogenic cells (supporting cells)
* function
**Sustentocytes or Sertoli Cells **
* Assist in sperm production by
1. carrying nutrients
2. move spermatogenic cells
3. phagocytize the shedded cytoplasm
4. secrete testicular fluid to push sperm out
Cells that contract rhythmically
* Function
Myoid Cells
* squeeze sperm & testicular fluid out of the testes
Cells that make and secrete androgens => testosterone
Insterstitial Cells of Leydig
Function of Testosterone
* Secretions and effects are controlled by
Maintain male sex characteristics and sex organs
* Controlled by the Lutenizing Hormone (AntP)
Left Testicular v drains to the __
Right Testicular v drains to the __
Left Testicular v => L Renal v
Right Testicular v => IVC
