Embryology Test 1 Vocab Words

Invagination

Infolding of a region of cells (like the indentation of a rubber ball).

Involution

- Inward movement of an expanding outer layer so that it spreads over the internal surface of the remaining external cells (blastopore).

Convergent extension

 - Cells lengthen by sliding over each other and expanding.

Amoeboid motion

- Movement due to filopodia of individual cells.

Intercalation

 - 2 layers fuse into 1 layer and spread laterally.

Ingression

 - Migration of individual cells from the surface layers into the interior of the embryo

(mesenchymal cells) (junction cells, not attached to anything).

Epiboly

 - Movement of epithelial sheets (usually ectodermal cells), which spread as a unit (become thinner and multiply) to enclose the deeper layers of the embryo.

Delamination (Polyingression)

 - Splitting of one cellular sheet into two sheets that are more or less parallel 

(formation of primary hypoblast) (chicks).

Synkaryon

Pronuclear fusion results in a diploid zygotic nucleus

Pronucleus

A new nuclear membrane

Sperm aster

Centrioles that enter with the nucleus form a sperm aster and push pronuclei together

Follicular phase

follicle development through ovulation

Luteal phase

 ovulation through degeneration of the corpus luteum

Menses (menstrual flow)

Epithelial lining of uterus (=endometrium)degenerates and sloughs off

Proliferation

Basal endometrium (stratum basale) thickens,spiral arteries and spiral glands develope

Secretory Phase

• (Uterus) Increase estrogen and progesterone from corpus luteum causes endometrium to vascularize

• Spiral glands secrete CHO-rich fluid (=uterine milk) to nourish embryo

• Highly vascularized tissue

Secretory phase

• if estrogen and progesterone levels drop, prostaglandins (PGF2A) causes spiral arteries to constrict

• Necrosis leads to release of lysosomal enzymes to degrade stratum functional (upper endometrium) 

  • leading to menses (ESG tells it to continue on the corpus luteum to produce estrogen does not become cor