Biology 213W - 02-12-24 | Quizlet

Gastrulation

a series of cell and tissue movements in which the blastula-stage embryo folds inward, producing a three-layered embryo, the gastrula.

Layers of gastrulation

ectoderm, endoderm, mesoderm

Acrosome

vesicle at the tip of a sperm cell that helps the sperm penetrate the egg

Zona pelllucida

glycoprotein layer surronding the plasma membrane of mammalian oocytes

Corona radiata

layer of granulosa cells from the follicle in the ovary

Polyspermy

fertilization by more than one sperm

Acrosomal reaction

binding triggers enzyme release

Acrosomal enzymes

digest the zona pellucida

Fast block

potential difference -70vM, fertilizing sperm enters and potential shifts to positive

Depolarization

Loss of a state of polarity; loss or reduction of negative membrane potential

Slow block

sperm penetration triggers the cortical granules to releases enzymes and create a physical barrier that pushes any remainding sperm away

Cleavage

cell division, mitosis, rapid, no growth, multicellular embryo

Blastula

hollow ball of cells

Organogenesis

organ formation that takes place during the first two months of prenatal development