Male reproduction o Testicles must descend or male will be infertile o Healthy sperm can only be produced at several degrees below body temperature Long term heat reduces sperm count o o Alcohol and marijuana cause serious reductions in sperm count short term Injury to the testicles o Repeated injury can cause scar tissue Can cause long term injury o Premature ejaculation o Erectile problems Female reproduction cervix Gravity o Cervix o The best way to get pregnant is for semen to be right against the Glands secrete thick mucous that blocks the cervix most of the month Protective layer Cervical hostility Impedes the movement of sperm cells Mucous doesn t thin out so sperm can t get through o Uterus About the size of a fist normally Endometrium Interior lining of the uterus wall Must engorge with blood to receive the fertilized egg blastocyst from the fallopian tube Implantation o Endometrium must thicken for implantation to take place o About 50 of fertilized eggs fail to implant o Takes about a week before implantation occurs Conception is a week earlier Pregnant is when implantation is successful Causes of infertility Endometrium doesn t engorge with blood Endometrial cells go up into the fallopian tubes instead of leaving with period o They replicate Endometriosis Leading cause of infertility in women likelihood increases with older women Most issues can resolve themselves o Fallopian tubes About the size of a strand of spaghetti Tiny muscles in the tubes have cilia attached and move the eggs along Can be destroyed easily by STD s No protection Susceptible to damage o Ovaries You re born with all the eggs you ll ever have The hypothalamus stimulates the pituitary gland Follicle stimulating hormone stimulates the ovaries to begin to ripen and mature some eggs Luteinizing hormone causes ovulation when its levels spike Too little of either hormone can cause infertility The surface of the ovaries should be clean and smooth The surface scars every time you ovulate Polycystic ovary syndrome PCOS o In about 5 10 of women o Present at birth progresses with age o Leading cause of infertility in women The Menstrual Cycle Lots of variation among and within individuals o o Not menstruating generally means infertility Causes for infertility Little body fat or too much body fat o Estrogen is produced by fat cells o o Follicular phase Luteal phase First half of your cycle Second half of your cycle o Ovulation generally occurs on the 14th day of the cycle on average Body temperature changes During the follicular phase body temperature is about 5 degrees lower than during the luteal phase Increases the day after ovulation Can also do a blood test to measure levels of hormones o Estradiol After the egg is released from the follicle the follicle produces estradiol Causes the endometrium to thicken Thickest at about day 21 Implantation occurs o Progesterone The follicle becomes the corpus luteum and produces progesterone Causes endometrium to thicken Prenatal Period Placenta degenerates and doesn t supply nutrients and oxygen for baby o Conception to birth o Normal pregnancy is 266 days o Over 280 days is post mature o Premature Can survive at 26 weeks o Prenatal stages Generally broken down into trimesters o Krantz breakdown First 2 weeks after conception implantation occurs during the first week Period of the ovum or zygote Implantation o Ball of cells called a blastocyst o 3 layers of cells Endoderm mesoderm ectoderm o The blastocyst flattens out then rolls back into a Where it meets is where the neural tube ball will form o Anencephaly Baby will be born without a functioning brain Neural tube defect Doesn t close fully o Spina bifida The bottom of the neural tube doesn t close and is exposed outside the baby Can be repaired in the womb now Exposed spinal cord causes varying degrees of mental retardation and paralysis from the waist down o Neural tube disorders can be reduced by about 50 if a woman s folic acid intake is increased before conception Embryonic stage Until the 8th week o Baby is referred to as a embryo Organogenesis o Process by which all the organ systems of a baby are formed structurally o Genitals will develop about a month later fetal stage o Each organ system has a critical period of development The placenta o Made of the baby s tissue o Mom s blood and baby s blood don t normally mix o Some diseases manage to get across the placenta o Thalidomide Was able to cross the placenta and caused babies to be born without arms or legs and varying degrees of mental deficiency Taken to avoid morning sickness Taken for leprosy and cancer o Found out that the placenta doesn t stop anything from crossing from the mother into the baby Teratogens o Harmful substances that can affect a baby o Babies don t have immune systems until they re about 6 months old o Babies livers and spleens are very immature and can t cleanse the blood stream and break down toxins o Cigarette smoke Lowers the birth weight of the baby growth retardation Higher rate of sudden infant death syndrome SIDS o Alcohol Alcoholics drink about a pint of liquor a day Fetal alcohol syndrome FAS Fetal alcohol spectrum disorder Causes facial abnormalities Leading cause of preventable mental retardation About 1 of babies in the US have FAS There is no acceptable level of alcohol during pregnancy o Antibiotics o Parasites Toxoplasmosis Causes visual impairment in babies Can do damage in adults with compromised immune systems o Herpes Can cross the placenta but is very unlikely It is more probable that during birth the baby will be infected o CMV Very prevalent in daycares Most people have it young and build up antibodies to it and become immune o Mercury o Phthalates Pollutant that s very active in the atmosphere In food especially fish What makes cosmetics smooth and able to be applied smoothly Makes estrogen levels higher and affects genital development of developing male fetuses The base for nail polish Damages internal organs Can do low levels of neurological damage o Toluene o Pollution and radiation o Accutane Drug for cystic acne A few applications can kill a baby Must also be prescribed birth control pills and sign waivers and take monthly blood tests o DES Given to prevent miscarriage Found out that it had no effect in preventing miscarriage but instead caused miscarriage in the offspring Causes vaginal or cervical cancer at very young ages Causes multiple reproductive problems in females born after the mother used
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