The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.
-
Upload
juliana-jennings -
Category
Documents
-
view
219 -
download
1
Transcript of The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.
![Page 1: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/1.jpg)
The Testes •Gamete Development (sperm)•Hormonal Production
(testosterone)
Male Reproductive Biology
![Page 2: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/2.jpg)
The Sperm’s Journey
• Spermatids released into lumen of seminiferous tubules
• Move through tubules• Stored in Epididymis
![Page 3: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/3.jpg)
The SPERM
Middle piece
Head
Tail
Enzymes dissolve
egg membrane genetic material
microtubules (cilia and flagella)
![Page 4: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/4.jpg)
Seminal vesicles & Prostate gland: Provide seminal fluid Cowper’s gland: Provide pre-ejaculatory fluid (lubricant)
![Page 5: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/5.jpg)
![Page 6: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/6.jpg)
Erection
•Facilitates penetration•Occurs when sexually aroused (mostly)•Mechanism: artery dilation filling of corpora
VIAGRA: •Not an aphrodisiac •Sildenafil increases levels of cGMP which causes
vasodilation of the corpora•Without sexual arousal, it can not cause an erection
![Page 7: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/7.jpg)
Male Hormonal Functioning
![Page 8: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/8.jpg)
Male hormonal function
HYPOTHALAMUS
PITUITARY
TESTES
GnRH
LH FSH
TESTOSTERONE
FSH -> + spermatogenesis
LH -> + testosterone
testosterone -> - GnRH.
![Page 9: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/9.jpg)
Testosterone• Sperm maturation• development of penis and testes• Male secondary sexual characteristics
– Axillary hair, – larynx, – oil and sweat gland secretion
• Threshold for sexual activity and libido• muscle anabolism
• Risk of prostate cancer
![Page 10: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/10.jpg)
![Page 11: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/11.jpg)
Testosterone and Aggression• Differences in testosterone don’t tell us
about individual differences in levels of aggression
Individuals with more T not more aggressive
![Page 12: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/12.jpg)
Effect of Social cues on hormonal and sexual behavior
The sexually dominant male (bottom) has vivid coloration and special markings.
![Page 13: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/13.jpg)
HYPOTHALAMUS
ANTERIOR PITUITARY
OVARYFollicle
FSH LH
Estrogens
GnRH Follicular phase
(first half of cycle)
Female reproductive biologyMenstrual Cycle
![Page 14: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/14.jpg)
Estrogen effects• increases progesterone receptor density in
breasts
• Initiates proliferative phase in uterus
• Causes changes in cervical mucous
cervix closes soon after ovulation
tangled fibers to line up, allowing sperm to get
through
![Page 15: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/15.jpg)
Copyright © Allyn & Bacon 2004
![Page 16: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/16.jpg)
![Page 17: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/17.jpg)
HYPOTHALAMUS
ANTERIOR PITUITARY
OVARY
Follicle Corpus Luteum
UTERUS
FSH LH
ProgesteroneEstrogens
GnRH
Endometrium, Cervix, Vagina
![Page 18: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/18.jpg)
• P is secreted by the Corpus Luteum after ovulation
• Increased concentration in breast in luteal phase– increases tenderness– increases nipple sensitivity
• Initiates secretory phase of endometrium– Heavy vascularization– Secretion of nutrient rich medium for embryonic growth
• Signals the pituitary to stop producing LH
Progesterone Effects
![Page 19: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/19.jpg)
Secretory Phase of Uterus
![Page 20: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/20.jpg)
• No fertilization– Corpus Luteum regresses after about 12
days– Progesterone products drops off sharply– Endometrium sloughs off (menstruation)
• Fertilization– Corpus luteum remains active– Progesterone levels remain high uterine
lining remains strong– Implantation occurs– hCG from fetus takes over
![Page 21: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/21.jpg)
• In rabbits, the act of coitus stimulates the pituitary gland to release gonadotropin which induces ovulation & increases the probability of pregnancy.
![Page 22: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/22.jpg)
![Page 23: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/23.jpg)
– Organizational effect:• The effect of a hormone on tissue differentiation and
development.
– Activational effect:• The effect of a hormone that occurs in the fully developed
organism; may depend on the organism’s prior exposure to the organizational effects of hormones.
![Page 24: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/24.jpg)
defeminization masculinization
![Page 25: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/25.jpg)
Copyright © Allyn & Bacon 2004
Vomeronasal organ (VNO):, mediates the effects of some pheromones
Lesion to VNO: female rat fails to recognize male as suchBehaves as maleThis suggests bipotentiality of adult female brain (male/female)
Pheromone:A chemical released by one animal that affects the behavior or physiology of another animal; usually smelled or tasted.
![Page 26: The Testes Gamete Development (sperm) Hormonal Production (testosterone) Male Reproductive Biology.](https://reader036.fdocuments.net/reader036/viewer/2022062519/56649dab5503460f94a9932f/html5/thumbnails/26.jpg)
– Effects of Pheromones• female animals housed together -> stop estrous cycle• synchronization of estrous cycle by pheromone in a
male’s urine.• female animals housed with males -> early onset of
puberty • Termination of pregnancy when new male other than the
one that impregnated the female.