Life-span development chap 4 notes

I. Prenatal Development A. Germinal Period - Conception to 2 weeks 1. Creation of the zygote 2. Continued cellular telephone socio-economic class 3. Implantation - attachment of the zygote to the uterine wall (10 date later founding) * Blastocyst - inner cells (embryo) * Trophoblast - outer layer (placenta/ umbilical cord cord - life aids placements) B. Embryonic Period - 2 to 8 weeks after conception 1. Cell differentiation intensifies, support systems for cells form and organs expects 2. committed zygote becomes embryo * entoblast (digestive/respiratory systems) * Mesoderm (circulatory system, bones, muscles, excretory system, rejoinder system) * Ectoderm (nervous system sensory receptors, skin parts such as cop and nails) C. Fetal Period - 8 weeks after conception until pitch 1. Fetal size increases and organs start functioning 2. Reflexes appear and thither is sexual differentiation D. Miscarriage and Abortion 1. around occur within 1st trimester (chromosomal abnor malities) 2. 15-20% pregnancies expiry in miscarriage * male fetuses more likely to miscarry 3. Abortions legal in U.S. until stamp out of 2nd semester * 1 spontaneous abortion for every 2 bears * cast-off(prenominal) pregnancies stressful for woman regardless of how it is contumacious * Psychological effects of abortion include relief and unrighteousness (usually mild and disappears) * Women with previous psychiatrical problems more likely to contract adverse effects II. Teratology and Hazards to Prenatal Development A. Teratogen - whatever constituent that yards birth defects 1.

Environmental Hazards * Radiation (chromosomal abnormalities) * Po! llutants & toxic wastes (lead, pesticides, ascorbic pane of glass dioxide, mercury dangerous to fetus) * Drugs Thalidomide - prescribed in 1960s for morning complaint (deformed babies) Cocaine/heroin (addiction/withdrawal symptoms/neurological defects) Alcohol (fetal intoxicant syndrome) Smoking (low birth weight, ADHD, wrong births, SIDS) Marijuana, antibiotics, excessive vitamins, antihistamines, aspirin, diet pills insalubrious 2. Maternal diseases can cross the placenta barrier and cause birth defects - Rubella (German measles)... If you want to get a bountiful essay, set it on our website: BestEssayCheap.com

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