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Developmental Biology > Cleavage > Flashcards

Flashcards in Cleavage Deck (20):
1

What is cleavage?

Series of cell divisions of zygote that occur without cell growth or separation 

2

blastomere

daughter cells generated from cleavage divisions

3

What is a morula?

solid ball of cells created from early cleavage divisions

4

What is a blastula?

hollow fluid-filled ball of cells forme as water flows osmotically towards center or morula. 

5

what is a blastocoel?

cavity formed in blastula. important for future development of organisms

6

karyokinesis

sepearation of chronosomes into two cells

7

cytokinesis

division of cytoplasm into 2 cells, facilitated by microfilaments

8

what are the two components of cleavage?

karyokinesis and cytokinesis

9

holoblastic cleavage

(complete cleavage) yolk doesn't play much of an influential role because there isn't much of it. Instead, cleavage can go all the way through the egg

happens in isolecithal and mesolecithal eggs

10

isolecithal 

sparce, evenly-distributed yolk

11

mesolecithal

moderate vegetal yolk distribution, affects rate of cleavage

12

meroblastic cleavage

(incomplete cleavage) parts of egg are not cleaved because of the large amount of yolk 

happens for telolecithal and centrolecithal eggs

13

telolecithal

dense yolk throughout most of the egg 

14

centrolecithal

yolk in center of the egg

15

What is gastrulation?

series of movements of individual cells and sheets of cells that accomplishes at least three important developmental objectives

16

accomplishments of gastrulation

  1. Generates 3 germ layers
  2. Establishes bilateral symmetry
  3. Establishes new and unique cell interactions which influence future developmental events

17

What process of gastrulation develops germ layers?

ingression

18

What are cadherins?

family of cell-cell adhesion molecules that hold cells of blastula togehter as a sheet 

19

aboral

side of developing organism away from mouth. like dorsal (as opp. to ventral)

20