Bio reproductive sys. Flashcards
seminiferous tubules:
importance cells participating in sperm prod.
-sertoli cells
-gemrs cells
-sertoli cells: promote sperm prod. + control germ cell development
-Germ cells: cells that goes through spermatogenesis
Spermatogenisis:
Where, when?
reduce why?
Spermatogonium
seminiferous tubules+ start at puberty
reduce with age after 35, smoking
immature germ cell that goes through meiosis to = 4 mature sperm
Spermatogenisis:
Steps
- Spermatogonium divides to form 2 identical cells. Only 1, the primary spermatocyte goes through spermatogenesis
2.Primatocyte divides (meiosis) + reduce number chromosome in half = second spermatocyte
3.secondary spermatocytes continue meiosis which produce 4 spermatids - Spermatogenesis (maturation process) transform spermatids u=into 4 mature sperms
anatomy sperm:
Head: contains chromosomes, covered with acrosome -contain digestive enzyme (important for fertilization)
mid-piece: energy center ATP created, energy powers the tail
Tail: Flagellum that beats to propel sperm through female reproductive sys. to meet egg
Path of sperm:
-sperm travel from seminiferous tubules to epididymis:
-coiled tube where sperm cell mature (12 days)
-smooth muscle contraction push sperm forward until m love on it own
- mature cells sperm stored in epididymis until ejaculation
During ejaculation sperms follow a serie of ducts until reach penis:
1. Vas deferens
-begins in scrotum+ extend into abdominal cavity
-vasectomy: cutting + sealing section of vas deferens prevent sperm exit scrotum
Fluids in semen:
-1 seminal vesicles
fluid procuced delivered into last part vas deferens
seminal fluid contains Fructose (sugar) sustain tail movements
during ejaculation sperms follow a serie of ducts until reach penis:
2.Ejaculatory duct
-sperm + seminal fluid continu their way inside ejaculatory duct
makes link btw vas deferen + urethra
meeting point with prostate gland
Fluids in semen:
-2 alkaline in prostate glang
contertact acidic PH of vagina
prostate dissorders:
BPH benigh prostate hyperplasia
prostate cancer
Fluids in semen:
-3 bulbouvethral gland
produce fluid lubricate ends of urethra + clean urine residues, released during arousal
male produced hormones:
testosterone
-functions (3)
-know feedback loop
steroid hormone produced by leydig cells of testes.
1.initiate physical changes at puberty + spermatogenesis
2.keep reproductive sys. working properly
3. muscles development, bone growth, sex drive (male and female)
Vuval:
1.mons pubis
2 labia majora
2 labia minora
4.clitoris
5. hymen
6 vaginal opening
1.layer of fat found over pubic bone, covered with pubic hair
ovaries:
female oocyte
oocytes develop in ovary inside ovarian follicules
produce sex hormones
utherine tubes:
-guide oocyte from ovaries to uterus
-not physically link to ovaries
-have fimbriae to “catch” secondary oocyte opon release
-fertilization of secondary oocyte by sperm
uterus:
3 sections
utherine wall (3)
-muscular organ supports growth embryo
-devided 3 sections:
1.fondus (superior)
2.body (middle)
3.cervix (inferior)
utherine wall:
1 Permetrium: connective tissues (outermost layer
2.Myomentrium: smooth muscle layer that contracts during delivery menstruations
3.endometrium: implation site for zygote (inner most layer)
Oogenesis:
-when
steps:
-start during fetal dev. stops and restart puberty
1.During fetal dev. oogonium devices + forms primary oocyte. process stops until puberty
2. LH stimulates oogenesis to continue + primary oocyte transform into secondary oocyte and polar body
3. once a month, secondary oocyte released from ovary at ovulation
4. mature ovum, if fertilized, become first cells of zygote
Ovarian cycle:
follicular phase
1.Hypo produces GnRH reaches ant. pit.
2. Ant. pit. produce FSH + LH send it blood stream
3. FSH reaches ovaries + stimulates follicles grow
3b. LH reaches ovaries + stimulate prod. estrogen. follicles growth increases prod. estrogen increases concentration in blood
4. High estrogen concentration detected by hypo = stop GnRH. Ant. Pit. stops FSH and LH
5. one dominant follical survives + it will release oocyte at ovulation
ovarian cycle:
ovulation
- dominant follicule continues secrete estrogen
2.ant. pit. seret large amount FSH + LH - burst of LH reactivates oogenesis + primary oocyte becomes secondary oocyte. LH triggers expulsion of secondary oocyte from follicule (ovulation
Ovarian cycle:
Luteal phase
1.cells becomes the corpus luteum (endocrine structure)
2. corpus lutuem produces large amount progesterone
3.progesteron triggers negative feedback loop decreasing GnRH, FSH, LH
4.If not prego+ corpus luteum disintegreates = stops producing progesterone
5negative feedback loop stops GnRH, FSH, LH start again. new cycle starts
Path of secondary oocyte
1.after ovulation, secondary oocyte must enter fallopian tube (by fimbriae)
2.smooth muscle contraction + beating cilia puch secondary oocyte towards uterus
3. on the way to uterus, fertilization happens
4.Becomes mature ovum, then zygote
5. first cell division start inside fallopian tubes as zygote go to uterus
6.zygote NEED to implant itself into endromitrium to continue growth
-successful implatation= signal corpus luteum to secrete more progesterone = pregnancy
-no implatation= no signal sent, it dies, endometrium becomes thinner+ shed = no pregnancy
Menstruation cyle:
1. Menses phase
2. Proliferative phase
3. Secretory phase
1.endrometrium is shed with unfertilized secondary oocyte
-last around 5 days
-progesterone+ FSH + LH= low
2.endometrium grows again stimulated by more estrogen concentration
-ovulation typically happens on day 14
3.Progesterone produced by corpus luteum initiates secretory phase
-endrometrium gets thinker, ready receive developing enbryo
-if not back to phase 1
in vitro fertilization
1.egg collection by ulrasounds + seringe
2sperms cell collecting by parner/bank
3.egg + sperm mix in petri dish or sperm in egg
4. embryo incubated until grow enough
5.embryo transferred women uterus
Hormones of pregnancy:
1.Estrogen (6)
-produced by placenta
-supress FSH + LH (prevent ovulation)
-induce fetal tissues growth + maturation of organs
-Promote fetal viability
-control progesterone production
-stimulates maternal tissue growth
Hormones of pregnancy:
2.Progesterone (4)
- produced by corpus luteum, later by placenta
- promote growth endrometrium
-suppress FSH + LH production
-Inhibit uterine contractions
Hormones of pregnancy:
3.hCG (human chronic genodotropin) (3)
-Produced by placenta after implentation
-detected by pregnancy test
- promote survival of corpus luteum
Hormones of pregnancy:
4.Relaxin (2)
-secreted by corpus luteum + placenta
-increased elasticity of joints + ligaments
Hormones of pregnancy:
5. Prolactin
stimulate enlargement mammary glands
stages of childbirth:
1.cervical dilatation
2. Expulsion of newborn
3.Afterbirth
