CSU Northridge, BIOL 482

Excerpt: ... cycle? The clock/Circadian rhythm Triggering, telling those cells not to produce the block the production of the receptors. You don't get that in males because they are day by day. Does this hormone actually influence the estrogen levels? Fsh and lh? If they go out and somehow change the estrogen levels? When they're growing up because they actually affect the levels, there is a delay. If this goes up, then this will follow. Lh and fsh directly influence the estrogen production but also whatever enzymes are required for ovulation Animal Phys Exam III 12-06-07 5 After ovulation the negative feedback of estrogen kicks in, causing a huge drop in levels of gnrh, fsh, and lh. Gnrh - it's gonna trigger production of lh and fsh Levels of estrogen here come negative feedback which is why you see this huge decrease in lh and fsh. The follicle cells continue with endocrine function and become corpus luteum Kind of milky, yellowish color becomes an endocrine organ w/o a trigger. Lh/fsh play no role, as y ...

Washington, PSYCH 357

Excerpt: ... very low levels of estrogen stimulate the production and release of GnRH. A. True B. False 15. According to the research of Roberts et al., men judge a woman's face as more attractive when she is in the luteal phase than when she is at midcycle, the time when she is most likely fertile. A. True B. False Multiple choice: Select the SINGLE most correct answer. (1 point each) 16. Which of the following is influenced in the SAME way by both natural progesterone and natural estradiol in adult women? A. rate of fat storage B. food intake and appetite C. blood pressure D. both A and B E. both B and C 17. Which of the following is TRUE of the corpus luteum ? A. Prolactin stimulates the formation of the corpus luteum . B. Progesterone is the hormone produced in the greatest quantity by the corpus luteum . C. Although the quantity produced is very small, the corpus luteum is THE major source of androgen for women. D. During the preovulatory phase of the monthly cycle, the corpus luteum produces estradiol in response to ...

Cal Poly Pomona, BIO 301

Excerpt: ... BIO 301 HORMONES FEMALE CYCLE 1. FSH (pituitary) stimulates ovarian follicles in ovary a) group of 1020 respond ("egg of the month") i) one develops faster like chicks in a nest; this one becomes Graafian Follicle ii) all produce estrogen a) estrogen causes endometrium to build up (Proliferative Phase) b) after certain level reached, get negative feedback and FSH stops c) Graafian follicle also produces Inhibin which supplements negative feedback High estrogen signals pituitary to release LH a) Rapidly dumps in LH ("LH Blip") then drops off equally rapidly i) This causes ovulation: egg bursts out of Graafian follicle a) Some women feel this "Mittleschmerz" (caused by blood from ovulation site irritating peritoneum) b) GF cells change under influence of LH to become the Corpus Luteum (1) Corpus luteum then produces progesterone, estrogen, and inhibin (Secretory Phase) (a) Progesterone causes cells in endometrium to change; become storage sacks w/sugar and other nutrients ( ...

Berkeley, BIO 1A

Excerpt: ... thing just kind of oozes out. The oocyte and the cumulus oophorus escape the ovary. At the time of ovulation, the stimulus for ovulation also causes the completion of meiosis I, and the primary oocyte divides and becomes the secondary oocyte (and you get a polar body). If you look inside the cytoplasm, you can see the chromosomes and the mitotic spindle. The secondary oocyte starts meiosis II, but gets arrested in metaphase, so that is why we see mitotic spindle. So now the oocyte has escaped the ovary. It is going to be picked up by the fallopian tube and travel towards the uterus. But, what happens inside the Page 8 of 12 ovary? Inside the ovary, the collapsed follicle undergoes a morphological differentiation into a new structure, called the corpus luteum . So the one huge Graafian follicle collapses, and the cells mature into a new cell type, called luteal cells, and we have a new structure called the corpus luteum . Both the granulosa cells and the thecal cells surrounding them become luteal cells. The ...

Alaska Anch, BIOL 112

Excerpt: ... phases formal definition: follicle oocyte (immature egg) + surrounding layer(s) of cells surrounding cells are called 1) follicle cells if only a single layer is present 2) granulosa cells if more than one layer Follicle stages 1) primordial follicle one layer of follicle cells 2) primary follicle two or more layers of granulosa cells; no fluid-filled spaces 3) secondary follicle fluid-filled spaces between granulosa cells 4) vesicular (Graafian) follicle large fluid-filled antrum is present and oocyte sits on stalk of granulosa cells Ovulation: one vesicular follicle ruptures at surface of ovary to eject 1 ovum each ~ 28 days (month) ruptured follicle becomes corpus luteum , which degenerates over the next 14 days to form corpus albicans (white body) Female ducts 1) oviducts (uterine tubes, Fallopian tubes) "connect" ovaries with centrally located uterus ovary and oviduct are not continuous; ovum is "picked up" by fimbriae of oviduct peristalsis and beating of cilia move ovum toward uterus ...

Colorado, EBIO 1220

Excerpt: ... help neutralize acidic urine left in urethra Urethra Average ejaculate - 2-5ml semen, 50-130 million sperm! Human female reproductive anatomy Oviduct Ovary Uterus (Urinary bladder) (Rectum) Cervix (Pubic bone) Urethra Vagina Bartholin gland s Shaft Glans Prepuce Labia minora Vaginal opening Labia majora Clitoris Oogenesis released during ovulation present at birth Ovaries Oviduct Follicles Uterine wall Endometrium Corpus luteum Uterus Cervix Vagina Important differences between spermagenesis and oogenesis 1) During meiotic divisions in oogenesis - cytokinesis is not equal, secondary oocyte is large, polar bodies degenerate 2) Sperm generated throughout a lifetime, while females have all their oocytes at birth 3) Oogenesis has "rest" periods, while sperm is continuously made Hormonal control of reproduction Male androgens, produced by Leydig cells of the testes responsible for primary and secondary sexual differentiation in males Testosterone is the major pl ...

University of Illinois, Urbana Champaign, IB 202

Excerpt: ... is 3. a. testosterone has negative effects on GnRH b. testosterone has negative effects on LH & FSH c. Sertoli cells release inhibin which has negative effects on LH & FSH Steps for Ovulation Control 1. 2. 3. 4. GnRH released (hypothalamus) -> positive effect on FSH/LH (ant.pit.) FSH (and to a lesser extent LH) stimulates growth of follicle cells follicle cells release Estrogen When there are low levels of estrogen . . . negative feedback of E on GnRH, LH, FSH . . . but follicle cells keep growing 5. Follicle cells get big -> release lots of estrogen-> turns into a positive feedback where estrogen stimulates release of GnRH and LH 6. Hormone surge in LH, FSH, & E -follicles burst -> ovulation 7. burst follicles turn into the corpus luteum which release progesterone (and some estrogen) 8. increased levels of progesterone result in thickening of endometrium 9. if no fertilization, then the corpus luteum slowly degrades and leads to the shedding of the endometrium lining 10. If fertilization, then imp ...

Fayetteville State University, PSB 4731

Excerpt: ... ion and maintenance of corpus luteum in the ovaries of rats and mice Oxytocin: profoundly influences reproductive function in mammals-important during birth, causing uterine contractions when uterus is responsive to it. Suckling reflex: oxytocin is released into the blood in response to sensory stimulation from the nipple Gonadal peptide hormones: Mllerian inhibiting hormone (MIH), inhibin, activin, & relaxin MIH: inhibits development of the Mllerian duct system into internal female sex organs Inhibin: secreted by sertoli cells & granulosa cell; feeds back to block secretion of FSH from anterior pituitary; inhibin also inhibits the enzyme aromatase Activin: in both testes & ovaries; stimulates FSH secretion Steroid Hormones Adrenal glands & the gonads are the most common sources of steroid hormones in vertebrates Precursor to all vertebrate steroid hormones is cholesterol Steroid hormones are lipidsoluble and move easily through cell membranes; they are not very soluble ...

BC, BI 132

Excerpt: ... Anatomy & Physiology II Notes 5/3/07 Reproduction cont. Female Hypothalamus begins to release gonadotropin releasing hormone which releases gonadotropins that act of the ovaries FSH stimulates granulosa cells (cells around egg cells) to produce estrogen LH acts on thecal cells that produce androgens (testosterone) which are then taken up by the granulosa cells that convert it to estrogen Ovulation release of egg cell that has completed the first meiosis division and a few follicular cells with it After ovulation, the follicular cells that have been left behind become the corpus luteum (structure that produces progesterone) o Corpus luteum lasts for a few weeks, if pregnancy occurs it is maintained and continues to produce progesterone Menstrual cycle 28 day cycle (varies), beginning is the first day of bleeding, o Endometrium tissue layer that builds up in the uterus in preparation for pregnancy, breaks down and is shed if pregnancy does not occur leaves body during menstruation, highly vasculari ...

Toledo, BIOL 2170

Excerpt: ... Chapter 43 Review Animal Reproduction Asexual reproduction Sexual reproduction 3 steps Spermatogenesis Products Oogenesis Arrest of development Polar bodies Initiation of meiosis II in humans Ovarian cycle Follicle Corpus luteum Fertilization Sperm activation Blocks to polyspermy Development from zygote to blastula ...

UC Riverside, BCH 120

Excerpt: ... nt growth into primary follicles. FSH FSH + E2 Each cycle, one secondary follicle becomes dominant and continues growth. The rest undergo atresia. follicle wall Following ovulation, the granulosa cells of the follicle differentiate into the corpus luteum Fig. 13-2 REPRODUCTION IV. Female Reproduction A. The Ovarian Follicle B. The Hypothalamic-Pituitary-Ovarian Axis C. Hormonal Events of the Menstrual Cycle D. Some Hormonal Interactions During the Menstrual Cycle The Hypothalamic-Pituitary-Ovarian Axis HYPOTHALAMUS Under the influence of the central nervous system, the hypothalamus secretes GnRH. GnRH Dopamine (-) PITUITARY The thecal cells respond to LH by producing androgens which serve OVARY as substrates for estrogen production by the granulosa. The granulosa cells are the main target for FSH which stimulates follicle growth and estrogen production. The granulosa cells produce the peptide hormone, inhibin. ovu FSH lati o n In response to GnRH, some pituitary cells secrete FSH and others ...

Texas, PSY 333M

Excerpt: ... Prenatal Development Outline -To take notes directly on this page, double or triple line spacing *Most of the information for the Prenatal Development lectures will be provided by inclass software; thus only a brief outline is presented on which students may take notes during the software presentation. Attendance is extremely important. I. Reproductive Organs and Fertility Treatments A. Female -follicle -FSH & LH - corpus luteum -endometrium -estrogen, progesterone -menstruation B. Male -sperm -seminiferous tubules -epididymus -vas deferens -seminal vesicle -prostrate gland C. Fertility Treatments ($2 billion year business in 1994) -delay of parenthood decreases fertility rates, esp. for women 1. Pergonal (menotropin): Follicle Stimulating Hormone to overstimulate egg production (used to be derived from urine of postmenopausal Italian nuns) 2. Artificial Insemination: into uterus or fallopian tubes for sex selection: http:/www.microsort.net/ 3. In Vitro Fertilization: eggs harvested, then: a. fertiliz ...