Embryonic Development After fertilization, embryonic development progresses thro
ID: 54655 • Letter: E
Question
Embryonic Development
After fertilization, embryonic development progresses through three stages:
1. cleavage, during which the zygote develops into a blastula through extensive cell division;
2. gastrulation, during which three tissue layers are established by the dramatic rearrangement of cells, forming a gastrula;
3. organogenesis, during which the rudiments of organs develop.
The details of embryonic development vary by species, but the developmental sequence is consistent. Embryonic development has been studied extensively in a few species, including sea urchins, frogs, and chickens. All the images in this tutorial are based on frog development.
Explanation / Answer
Embryonic germ layers form.
Gastrula.
Neural tube
Somites.
Note:
Cleavage gastrulation organogenesis Cytoplasm portioned into many cells. Blastopore organs begin to develop from germ layers. Blastula.Embryonic germ layers form.
Gastrula.
Neural tube
Somites.