Repro 3 Flashcards
GnRH
Is secreted in a pulsatile manner
How is GnRH activated
- Pulsatile activity in kisspeptin neurons stimulate GnRH neurons to release GnRH
- GnRH binds to GnRH receptor on gonadotropes in the anterior pituitary to release LH and FSH
- LH and FSH act on gonads to stimulate hormone secretion and facilitate gamete production
Environmental factors influence reproduction
In looked in females
Nutritional factors
Level of physical activity
Circadian Rhythm
Environmental estrogens
can bind and activate estrogen receptors
Testes
Produces hormones and gametes
External genetalia in males
Penis
Urethra
Corpus Spongiosum (keeping the urethra open)
Corpova cavernosa (Creating erection)
Glans, prepuse (head of penis)
Scrotum
External sac testes migrate into
Sperm development requires lower body temperature
Internal genetilia
Accessory glands
What are the accessory glands
Seminal Vesicle
Prostate gland
Bublourethral gland
Function of internal genetilia
Empty secretions into the urethra
Prostate
Continually grows through a males life
What is responsible to the formation of external genetilia and prostate
DHT
Finasteride
DHT inhibition (Slows down Prostate hypertrophy)
What do testis produce
Sperm and Hormones
Bulk of tests mass is
Seminiferous tubule
What is the site of sperm production
Seminiferous Tubule
Leydig cell produces
Testosterone
Sertoli cells
Contains tight junctions with adjacent Sertoli cells forming a blood testes barrier between tubule lumen and interstitial space
Male pseudohemaphrodites
Lack the enzyme to convert testosterone to DHT
Sperm production
Germ cells (spermatogonium) reside just inside the basal lamina of seminiferous tubules
As spermatocytes differentiate to sperm they move towards the tubule lumen
Sertoli tight junctions break and reform around the migrating cells
Structure of sperm
Chromatin condenses
Microtubule extension
Acrosome forms a cap over the nucleus
Mid piece: Mitochondria for energy
Spermatogonium to free sperm
What is mid space composed of
Mitochondria
Where do sperm mature
epididymis
FSH binds to
Sertoli cells
LH tagets
interstitial leydig cells promoting testosterone production
Primary components of semen
Nutrients
Buffers
Chemicals to increase sperm motility
Prostaglandins
Immunoglobulins
The cells that primarily regulate spermatogenesis are
Sertoli cells
