6 FertilizationFraternal twins are the result of 2 different eggs fertilized by 2 different spermIdentical twins are the result of a single egg/sperm that subsequently splits into twins. These twins are genetically identical.Ectopic pregnancy is a pregnancy in an abnormal site, usually when the fertilized egg gets stuck in the oviduct
7 Cleavage Day 1-4 pregnancy Mitosis division that occurs in oviduct as embryo moves towards the uterus
13 Blastocyst Implantation occurs on day 7-8 Blastocyst burrows its way into mom’s endometrium for nourishment & protectionEmbryo secretes HCG, Human Chorionic Gonadotropin, that serves to keep the corpus luteum making estrogen and progesterone.
18 Gastrulation Germ Layers Ectoderm is outer layer destined to become nervous tissue and skin.Mesoderm is middle layer destined to become skeleton, muscles, heart, blood, vessels….Endoderm is inner layer destined to become lungs and digestive structures.
39 Fetal Amnion Sac surrounding fetus Filled with amniotic fluid that provides protection, facilitates movement, and keeps a warm temperatureAn amniocentesis is a sampling of this fluid checking for chromosomal and genetic abnormalities.
49 ChildbirthEstrogen causes minor contractions forcing the baby’s head against mom’s cervixStretching of the cervix causes the release of OXYTOCIN which causes large contractionsOxytocin is made in the hypothalamus but released from the pituitary