The new cell produced by fertilization is called a:

Direct transfer of nutrients and oxygen from mother to fetusoccurs primarily across which of the following?

A genetic male human has these chromosomes:

During capacitation the sperm:

Humans have _____ pairs of chromosomes:

Gastrulation is complete when:

During Gastrulation, the blastula folds in on itself to form three layers, the ______, _______ and ______.

An organism with two identical alleles is:

The blastocyst implants in the uterine wall with the assistance of:

The sperm contain enzymes such as ____ that enable the sperm to penetrate the egg: