HSCI 100 Chapter Notes -Inner Cell Mass, Neural Tube Defect, Human Chorionic Gonadotropin

• School: Simon Fraser University
• Department: Health Sciences
• Course: HSCI 100
• Professor: Nienke Van Houten

Document Summary

Cleavage: cells undergo mitotic division (2,4,8etc) w/o embryo increasing in size. Growth: cells undergo mitotic division & increase in size. Morphogenesis: embryo begins to take shape as cells migrate. Differentiation: when cells take on specific structure & function (nervous system first visible) Cleavage: mitotic cell division that increases # of cells, without increase in size. Morula: compact ball of embryonic cells (~32) Blastula: forms after about 1 week, creation of inner cell mass becomes embryo covered by layer of cells (trophoblast) that becomes chorion (so chorion is really first cell type that differentiates) Implantation: embryo embeds into uterus around day 6-16. Protect and nourish embryo & eventual fetus. Chorion: fetal half of placenta, organ provides embryo with nourishment & gets rid of wastes by exchange with mother"s blood. Allantois: gives rise to bladder & blood vessels of umbilical cord that carry blood to & from fetus.