Animal Development

Flashcards covering key concepts of animal development in deuterostomes, including terms related to gametes, fertilization, and embryonic development stages.

Deuterostome

An organism whose embryonic development includes forming an anus from the blastopore.

Gametes

Reproductive cells; Male gametes are called microgametes (sperm) and female gametes are called macrogametes (ovum).

Fertilization

The process of fusion between haploid gametes to form a diploid zygote.

Zygote

The single diploid cell formed by the fertilization of male and female gametes.

Cleavage

The process of mitotic cell division of the zygote leading to the formation of a morula and then a blastula.

Morula

A solid ball of 32 or 64 cells formed during early cleavage.

Blastula

A hollow ball of cells that forms from the morula and contains a fluid-filled space called the blastocoel.

Gastrulation

The process where cells move inward from the blastula, forming the gastrula and establishing the three germ layers.

Blastopore

The opening through which cells migrate during gastrulation, which becomes the anus in deuterostomes.

Ectoderm

The outer layer of the gastrula, which gives rise to the nervous system, skin, and certain organs.

Mesoderm

The middle germ layer that forms the skeletal system, muscles, and other internal structures.

Endoderm

The inner germ layer that gives rise to the digestive tract and associated organs.

Neurulation

The process following gastrulation where the nervous system begins to form from ectodermal cells.