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Reproductive System. Sexual Reproduction. Union of male and female gametes Asexual Reproduction Offspring produced by a single parent (ex. plants and fungi). Fertilization. Joining of an ovum and sperm zygote with 2n chromosomes
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Sexual Reproduction • Union of male and female gametes Asexual Reproduction • Offspring produced by a single parent • (ex. plants and fungi)
Fertilization • Joining of an ovum and sperm zygote with 2n chromosomes • http://www.youtube.com/watch?v=hAgOk3-loUY&feature=related Stages of Development • Zygote: fertilized egg • From fertilization to 2 weeks (from fallopian tubes to the uterus) • Embryo: 2 – 9 weeks • Fetus: 9 weeks to birth
Endometrium • Layer that lines the uterus • It will develop and shed depending on if fertilization occurred • Fertilization occurred: no period • Fertilization did not occur: period
Puberty • All the physical and psychological changes which occur to prepare the body for the ability to reproduce. • Occurs around ages 10-14 • http://www.bbc.co.uk/science/humanbody/body/interactives/lifecycle/teenagers/index.shtml?girlBrainGo
Hormones • Chemicals released by glands which travel in the blood. They target specific organs and cause changes to the organs. • Gland Hormone Change
Puberty Glands and Hormones Pituitary (master gland) FSH + LH (hormones, travel in blood) Follicle-Stimulating hormone and Luteinizing hormone Female Male
Puberty Glands and Hormones Pituitary (master gland) FSH + LH (hormones, travel in blood) Follicle-Stimulating hormone and Luteinizing hormone Female Male <- glands -> Estrogen and Testosterone secreted progesterone secreted Cause primary and secondary sexual characteristics Causetesticles to produce hormones and spermatozoa Causeovaries to produce hormones and ova to mature
Primary Sexual Characteristics Female Male
Secondary Sexual Characteristics FEMALE MALE BOTH
Female Reproductive System • 1) OOGENESIS • Process of ovum production by meiosis. • Follicle: layer of cells that surround oocyte. • Females are born with approximately 700 000 cells that CAN become ovas. • Meiosis has already begun when a female is born and has stopped at prophase 1. Once puberty has begun, meiosis will resume.
Oogenesis • Process of Oogenesis Primary oocyte – diploid – matures in follicle Polar body – have no cytoplasm and quickly die This oocyte will rupture from the follicle during ovulation and can be fertilized if sperm meets it.
Oogenesis • 1 oocyte gives 1 mature ovum • Meiosis 2 occurs after ovulation as ovum travells in Fallopian Tube • Mature ovum has all the cytoplasm
Oogenesis • Difference between oocyte and ovum? • Oocyte has not completely finished meiosis and cannot be fertilized. • Ovum is a mature egg which can be fertilized
2) Ovarian Cycle • Process where 1 ovarian follicle matures and changes into the corpus luteum. • Corpus Luteum: Remainder of the follicle after ovulation occurred and stays in the ovary.
http://www.youtube.com/watch?v=nLmg4wSHdxQ • Human ovulation on film • http://www.youtube.com/watch?v=2-VKgdhfNpY&feature=related
3) Menstrual Cycle: Periodic changes in the endometrium • http://www.youtube.com/watch?v=8_rfZ_qj1z4&feature=related • Definitions: • A) Ovulation: ovum released from ovary to Fallopian tube • B) Follicle: Layer of cells that surround oocyte – immature ovum
Menstrual Cycle • C) Corpus Luteum: remainder of follicle after ovulation • D) Endometrium: lining of uterus where blood vessels develop for implantation of zygote • E) Menstrual phase: Period • F) Proliferation phase: end of period to ovulation • G) Secretory phase: endometrium continues to thicken • H) Fertility period: time where ovum can be fertilized by sperm in FT. Approx 4 days.
Functions • LH: ovulation • FSH: causes follicle to develop • Progesterone: thickens endometrium • Estrogen: causes LH to be secreted • Follicle: secretes estrogen • Corpus luteum: secretes progesterone
Steps • Pituitary secretes FSH • FSH causes follicle to develop • Follicle causes estrogen to be secreted • Estrogen causes more FSH and LH to be secreted by pituitary gland • FSH and LH cause ovulation • Corpus luteum formed • Corpus luteum secretes progesterone
Steps … • Progesterone inhibits FSH and LH, endometrium thickens If Ovum not fertilized • Corpus luteum deteriorates • Progesterone decreases • FSH secreted and endometrium shed (period) • Start over again
Cycle • A cycle is around 28 days • Can be more or less, unless on oral contraceptives • On a 28 day cycle: • 1-5: period (menstrual phase) • 6-13: proliferation phase • 14: ovulation • 15-28:secretory phase
Cycle • If cycle is not 28 days. Menstrual and proliferation days vary. • Once ovulation occurs, period will come 14 days later (unless pregnant)
If egg was fertilized • Corpus luteum deteriorates • Progesterone levels stay high • Endometrium continues to develop • No period • ** HCG in urine is used to test for pregnancy
Calculating Period dates and Ovulation • A cycle begins day 1 of period. • When the next period begins, new cycle starts back at day 1. • Next period?: Count # of days in cycle from 1st day of period • Ovulation day: count 14 days back from first day of period
Menopause • Ovaries decrease then stop the production of estrogen and progesterone. • Ovulation and period will stop. • Could be gradual or sudden • When a female has not had her period for a year menopause • Side effects: hot flashes, insomnia, night sweats, mood changes
Answers a) Which gland starts off the process of puberty? pituitary b) Which two hormones, produced by this gland, stimulate the production of sex hormones? FSH and LH c) What hormone is produced in the testes?testosterone d) What hormones are produced by the ovaries? estrogen and progesterone
Memory Quiz a) Which gland starts off the process of puberty? b) Which two hormones, produced by this gland, stimulate the production of sex hormones? c) What hormone is produced in the testes? d) What hormones are produced by the ovaries?