Bio102 Exam 3 Professor Rebecca Wright

The increase and size and cell number in an embryo

The development of the shape of the embryo

The specialization of structure and function in cells

Allows the sperm to reach the surface of the egg

Fertilization by the other millions of sperm

Cell division in the absence of cell growth; increases the surface to volume ratio of each cell

Cells in the cleavage stage

Is a cluster of blastomeres that results from cleavage

The fluid-filled cavity of the blastula

(also called the archenteron) becomes the gut tube in the embryo

The opening from the outside into the gastrocoel; forms at the posterior end of the embryo in vertebrates near where the anus will be

Gives rise to the epidermus, brain and spinal cord; outermost germ layer

Middle germ layer; forms the notochord, a supporting rod just under the brain and spinal cord along the dorsal midline; gives rise to muscles and bone; gives rise to the circulatory system and blood

Innermost germ layer; forms the inner lining of the gut and the inner lining of other internal organs including the lungs

Formation of the brain and spinal cord