Biology 7 Lab Final Exam

Growth

irreversible increase in size of an organism

Differentiation

the structural and functional specialization of groups of cells

Morphogenesis

development of pattern, shape, and form

Embryology

the study of processes (such as growth, differentiation, and morphogenesis) in the early development of an organism

Fertilization

male and female gametes fuse to form a zygote`

Cleavage

zygote divides into a larger and larger number of smaller and smaller cells that eventually form a hollow sphere of many cells, ends when groups of cells begin to differentiate

Gastrulation

cells of the sphere formed during cleavage continue to divide and move inward to form 3 cellular layers

Holoblastic

cleavage of the entire zygote (only a small amount of yolk is present and easily divides evenly)

Morula

continued cleavage that forms a ball of 16-32 cells

Blastula

hollow sphere of many cells

Blastocoel

the fluid-filled cavity within the blastula

Blastomeres

cells of the blastula

Ectoderm

outer layer of gastrula cells

What does the ectoderm eventually form?

eventually forms the skin and nervous system

Endoderm

inner layer of gastrula cells

What does the endoderm eventually form?

eventually forms the digestive tract

Mesoderm

forms between ectoderm and endoderm

What does the mesoderm eventually form?

eventually forms muscular tissue and parts of the reproductive and circulatory systems

Organogenesis

the development of organs

Animal Pole

the darkly pigmented hemisphere of the embryo that has less yolk

Vegetal Pole

the lighter hemisphere of the embryo that contains a significant amount of yolk