Exam 32: An Amazingly Detailed Script: Animal Development

A difference between a morula and a blastula is that the:

Which of the following is true of the animal pole of a zygote?

The archenteron is mostly made of the mesoderm.

You are a substitute teacher in a high school biology lab class on the day the students are dissecting frogs.A particularly bright student happens to notice that the left adrenal gland is malformed in her frog.She asks if a problem in embryonic development could have caused that.Although there may be more than one reason,what might you propose as an explanation based on embryonic development?

How long is the DNA in the homeobox sequence?

Early vertebrate embryos share a general similarity in shape in the period following somite development.

Which is true regarding somites in an embryo?

Migration of which of the following to different parts of the embryo produces various tissues and organs?

The mesoderm refers to the middle layer produced during gastrulation.

Cell death during development will always have negative,possibly fatal,effects on normal development.

Cleavage and gastrulation take place in animals such as humans and birds but not in frogs.

In chickens,the wings develop from a zone of polarizing activity (ZPA).

The lenses of the eye are produced from the endoderm.

You are a substitute teacher in a high school biology lab class on the day the students are dissecting fetal pigs.One student finds that his pig's lungs,liver,pancreas,and digestive organs are either missing or small and malformed.The student scratches his head with his clean hand and says,"What went on here?" Although there may be more than one reason,what might you propose as an explanation based on embryonic development?