Unit 5 Lecture 37 Flashcards
What is the male repro system composed of and identify their functions?
- Testes: produce sperm
- Ducts: store and transport sperm
- Accessory glands
- Supporting structures
What makes up the ducts of the male repro system?
- Urethra
- Ejaculatory duct
- Vas Deferens
- Epididymis
- ampulla of vas deferens
What are the accessory glands of the male repro system?
- seminal vesicle
- prostate
- bulbourethral (Cowper’s) gland
How much semen is secreted by the seminal vesicle and the prostate?
seminal vesicle - 60%
prostate - 25%
Compare the semen fluid in the seminal vesicle, prostate and cowper’s gland
seminal vesicle - viscous seminal fluid
prostate - thin seminal fluid
cowper’s gland - mucous like fluid
What is the viscous seminal fluid made of in the seminal vesicle?
Fructose, prostaglandins and fibrinogen
Function of fructose
fuel for glycolysis for ATP production
Function of prostaglandins
Contributes to sperm viability, motility and transport
Function of fibrinogen
Aids in coagulation of semen in female reproductive tract
What makes up the thin seminal fluid in the prostate?
proteolytic enzymes and seminalplasmin
Function of proteolytic enzymes
breaks down clotting proteins from seminal vesicles
Function of seminalplasmin
it’s an antibiotic that destroys bacteria
What makes up the mucous like fluid in the cowper’s gland?
alkaline fluid
Function of alkaline fluid
protects sperm from acids in urine
Label the path of sperm in the testes to epididymis
Seminiferous tubules –> straight tubules –> rete testis –> efferent ducts –> epididymis
What are the 2 types of cells found within the testes?
Sertoli cells and Leydig cells
Where are sertoli cells are what is their function?
Support sperm development within densely packed seminiferious tubules
Where are leydig cells and what is their function?
Found within interstitial connective tissue that produces TESTOSTERONE
Define spermatogenesis
*The overall process to make sperm
= the conversion of spermatogonia into specialized spermatozoa
Label the path from spermatogonia to spermatozoa (sperm cell)
Spermatogonia –> primary spermatocyte –> secondary spermatocyte –> spermatid –> spermatozoa (sperm cell)
What process must happen before the beginning of spermatogenesis?
Mitosis
Define mitosis
cell division that results in two types of daughter cells each having the same number and kind of chromosomes
After mitosis, what process begins spermatogensis?
Differentiation of the spermatogonium into a primary spermatocyte
What process happens after differentiation?
Meiosis I
What happens during Meiosis I?
1 (2n) primary spermatocyte becomes 2 (n) secondary spermatocytes
List the 3 unique events of meiosis I
- tetrad formation (synapsis)
- crossing over
- movement of pairs of chromatids towards poles
What process happens after Meiosis I?
Meiosis II
What happens during Meiosis II?
2 (n) Secondary spermatocytes becomes 4 (n) spermatids
What process happens after Meiosis II?
Spermiogenesis
What happens during spermiogenesis?
4 spermatids become 4 spermatozoa
What 4 parts make up the spermatozoa?
Acrosome, middle piece (mitochondrial sheath), nucleus and tail
Function of acrosome
facilitates penetration of SECONDARY OOCYTE
Function of middle piece/ mitochondrial sheath
Provides ATP for locomotion
Function of nuclues
contains 23 highly condensed chromosomes
Function of tail
propels sperm through female repro tract
Define spermiation
the release of mature spermatozoa from sertoli cells into the lumen of the seminiferious tubule
Define capacitation
final maturation of sperm
*occurs within female tract
What triggers capacitation?
secretions from the uterus
How does the sperm cell penetrate the matrix of the surrounding oocyte?
hyperactivation of tail
What causes hyperactivation of the tail?
Ca2+
What is Ca2+ the result of?
increased progesterone (produced by women) acting on the male sperm
What makes a man infertile?
they don’t have the progesterone-binding Ca2+ channels (CATSPER1 null)
At puberty, which hormone triggers increased production of LH and FSH?
GnRH (gonadotropin releasing hormone)
What does LH do?
stimulates secretion of testosterone by Leydig cells
What does FSH do?
promotes spermatogenesis through sertoli cells by stimulating ABP which keeps testosterone high
What is something else that sertoli cells release that reduces FSH?
inhibin
