Physiology Flashcards
What promotes the conversion to testes?
Testis-determining factor
What do seminiferous tubules produce?
Sperm
Sertoli cells
What cells secrete testosterone?
Leydig cells
When do the testes descend into the scrotum?
Shortly befor birth
Define Tunica Albiginea
Fibrous capsule of the testes
Define Tunica Vaginalis
Surrounding the seminiferous tubules
Define Testes
Egg-shaped structures outside the abdominal cavity in the scrotum
Where do the testicular arteries branch from?
Abdominal aorta
What helps to cool off the warm blood from the testicular arteries?
Pampiniform plexus
When do the testicles descend?
7-12 weeks fetal life
7-9 months fetal life
Why is testicular descent important?
Risk of hernias
Increased risk of testicular cancer
Function of the Scrotum
Houses testes
Muscles that Affect the Surface Area of the Scrotum
Dartos muscle (wrinkles) Cremaster (elevates)
Site of Sperm Production
Seminiferous tubules
Path of Sperm from Testes to Vagina
Seminiferous tubules Efferent ducts Epididymus Vas deferens (Ductus deferens) Ejaculatory duct Urethra (prostatic) Penis
How do sperm move from the efferent ducts to the epididymus?
Peristaltic movements
Seminal Vesicles
Secrete fluid high in fructose (energy for sperm to swim)
Excrete prostaglandins: increases muscle contraction & helps with cervical mucus
70% of semen fluid
Prostate Gland
Fibromuscular gland
Add fluid to the semen (make it more alkaline)
2 Issues with the Prostate Gland
BPH
Cancer
Bulbourethral Glands (Cowper Glands)
Helps to become more alkaline
Where does seminal fluid come from?
Genital ducts
Accessory organs
Define Penis
Shaft that ends in a tip
Define Glans Penis
Tip of the penis
Define Foreskin
Loose skin of the penis shaft folds to cover the glans
Portions of the Penis
Corpus cavernosa
Corpus spongiosum
Hormone Path to Leydig Cells
GnRH
LH
Gonads
Testosterone (negative feedback loop)
Hormone Path to Sertoli Cells
GnRH
FSH
Inhibin (negative feedback loop)
Endocrine Function of the Testes
Differentiation of male genital tract during fetal development
Induces development of primary and secondary sex characteristics
Anabolic effects
Promotes spermatogenesis & maturation of sperm
Stimulates erythropoiesis