Exam 43: Animal Development

The most rapid differentiation in an embryo occurs during the first 2 months of pregnancy.

is the developmental event that results in the formation of a primitive gut and the three tissue layers.

During development, some cells , or specialize in both structure and function.

The nervous system forms from the

If a cell lacks transcription factors, will never be transcribed.

The extraembryonic membrane that sends blood vessels into the endometrium is the chorion.

The birth defect spina bifida results in part of the spinal cord lying outside of the body. This defect is due to abnormal development of the

A human embryo has webbed fingers. Why are human babies not usually born with webbed fingers?

In the 1920s, two German embryologists, Hans Spemann and Hilde Mangold, demonstrated that a small patch of cells, called the dorsal lip of the blastopore, would

Newborn animals that closely resemble the adults of their species undergo development.

-The fluid the embryo floats in is produced by structure

Prior to birth, stretching of the cervix by the baby's head stimulates the release of

A _ is a fertilized egg.

The cells of an aging animal function less efficiently because

At which stage is the human embryo most susceptible to toxic substances?

Mitotic cell divisions of the zygote are collectively called cleavage.

The structure produced by cleavage of a human zygote is called a(n)

Which extraembryonic membrane lies immediately beneath the shell of a reptile embryo?

-Metabolic wastes may be stored within structure 4, the

Your biceps muscle is derived from the