Chapter 46 11 19 2015 MALE CONTINUED All negative feedback in the male FSH and LH are tropic hormones FSH goes into sertoli cells wall of seminiferous tubules o Sertoli either turns on spermatogenesis and Inhibin negative feedback on the anterior pituitary LH goes into Leydig cells o Lydig makes testosterone if testosterone gets too high will turn on negative feedback o Testosterone in turn starts spermatogenesis Gonadotropin releasing hormones GnRH Affects FSH and LH Made and sent out from hypothalamus Testosterone Released at the start of puberty Males make testosterone during final embryonic development Secondary sex characteristics develop Body shape beings to change addition of muscle mass Can increase aggressive behavior in non humans we have the ability to think about our actions FEMALES FIG 46 10 Two types of reproductive systems in female mammals Menstrual cycle o Humans great apes old world monkeys Estrus cycle o Defined by behavior o Dos is in heat o Female will not allow male to mate with her until she is in estrus because that is when she will most likely get prego o Females don t bleed endometrium sluffing off Pheromones Released from the animal Can be for defense skunk snake Can be involved in reproduction Chemical signals involved with knowing who is who Ovary Main organ associated with female Space between ovary and oviduct Cilia beats toward uterus to push the egg into the oviduct Fimbrea help make currents to bring eggs in FIG 46 12 production of eggs ovum oogenesis o Primordial germ cell mitotic divisions o Oogonium mitotic divisions o Primary oocyte completion of meiosis 1 and onset of meiosis 2 Secondary oocyte first polar body arrested at metaphase 2 Ovulation sperm entry Completion of meiosis 2 second polar body Fertilized egg Egg will never complete meiosis unless it is fertilized Run out of eggs menopause Granulosa cells line the follicle and the egg throughout maturity in the ovary o Get left in the ovary once follicle rupture and sends eggs out o Turns into the corpus luteum Clitoris is the embryonic equivalent of the penis Has erectile muscle Functional level built up towards lumen Basal level right behind functiona Ovary Fallopian tubes uterus Menstrual cycle Controlled by hypothalamus GnRH anterior pituitary FSH and LH Ovarian cycle o Typical cycle said to be 28 days o Day 0 day 14 follicular stage Developing the follicle o o o o Negative on FSH until development of estrogen raises and then a positive feedback FSH causes primary oocyte to start to grow Surge in FSH and LH for ovulation to occur o Day 14 Ovulation occurs LH loosens ovarian cells and allows cell to be released o Day 15 28 luteal phase LH important in maintaining corpus luteum gone by day 18 if pregnancy doesn t occur o peak of estradiol FSH peak LH peaks o corpus luteum produces progesterone negative affect on the pituitary hormones won t develop another egg during pregnancy Uterine cycle o Day 0 day 5 menstrual flow phase o Day 5 14 Proliferative phase Build up of tissues o Day 14 28 secretory phase Progesterone and estradiol really important here Increase in cells fluid blood vessels Secreting mucous Contains glycogen feed the egg until it implants 3 forms of estrogen that we produce estradiol is the main one animals that get pregnant easily rats cats llamas camels etc will most likely get pregnant every time the mate Induced ovulators the female is not going to release her eggs at ovulation until she mates Male cats have barbs on penis that scrape the inside of the vagina it is a good thing because it enacts the release of LH which induces ovulation Menopause Occurs somewhere around the 50s Decrease in the ability to become pregnant leading up to menopause Go through this because we run out of eggs Role of estrogen Development of secondary sex characteristics Testosterone levels have to do with sex drive Progesterone Pregnancy hormone Makes you want to eat Makes women nest clean everything Fertilization occurs in the upper third of the oviduct FIG 46 15 1 Ovulation 2 Fertilization 3 Cleavage 4 Cleavage continues 5 Implantation in endometrium trophoblast embryos contribution of the uterus human chorionic gonadotropic HCG o exactly like LH o goes up and tells the corpus luteum to stay so that it will continue to make progesterone FIG 46 16 First three months of pregnancy is when everything is going on BIRTH Fetus adrenal gland signal mom to say that they are ready to be born sends estrogen precursors to the placenta where it is then converted to make estrogen Changing a ratio higher estrogen levels for birth Oxytocin receptors on the uterus cause contractions and has a positive feedback on the oxytocin Oxytocin stimulates placenta to make prostaglandins that turns around and does positive feedback on the placenta Breast Originated from sweat glands Produce milk Start to develop at puberty bc of estrogen Alveoli sacs where milk is made Various numbers of opening in nipple so that milk can come out Only animals that keep breast humans Mostly adipose tissue After birth breasts are larger During pregnancy milk isn t made high levels of progesterone Oxytocin milk let down Prolactin released to make milk Positive feedback neuroendocrine response when baby is nursing more prolactin and more oxytocin strong nursers will get more milk milk will stop being produced after baby stops nursing IGA in breast milk Colostrum sticky yellowish fluid chalk full of IGA s first milk that is produced lot of protein but not a lot of fat skim milk Why we don t reject babies Not really sure All of the hormones involved with pregnancy might have an immunosuppressive effect Might have something to do with t cells Might get rid of tryptophan which suppresses the t cells FasL binds to receptors on the cytotoxic T cells and causes apoptosis First three months Anything that mom might be exposed to or anything she takes can have adverse affects on baby Every organ system has a critical period of development Lots of things that can cause birth defects o Alcohol causes very distinct facial development affects nervous system and learning diffuses very easily into the baby o Excess vitamin A in animals can cause birth defects o Phalidomi drugs women took in the 60 s when they were having trouble sleeping increase in birth defects in Europe Japan Australia babies born without arms legs affected prevented the growth of long bones only had to take it one time throughout the critical period of long bone development for