Exam 20: Development

All of the following occur during the pre-embryonic period EXCEPT

How long does the pre-embryonic period last?

What is the term for traits carried on the X and Y chromosomes?

Fertilization is the

What is the term for the series of mitotic cell divisions that begin shortly after fertilization?

All of the following occur during the embryonic period EXCEPT formation of

What is the term for the region of the blastocyst that develops into the embryo?

Implantation normally occurs

What is the term for the single cell that is the result of fertilization?

The outermost extraembryonic membrane that contributes to the formation of the placenta is the

The postnatal development period during which an individual is most vulnerable to environmental stresses is

What is the term for the cells that enclose a blastocele?

The appearance of secondary sex characteristics occurs during

The extraembryonic membrane that is the source of primordial germ cells is the

The expression of genes is called

All of the following are derived from ectoderm EXCEPT

The blood vessel that bypasses the lungs in fetal circulation is the

What is the term for the hair that covers the fetal body and helps keep the vernix caseosa in place?

Morphogenesis refers to the

The two fundamental processes that occur during the fetal period are