In a newly fertilized egg, the vitelline layer _____.

In fetal circulation the descending aorta carries the less oxygenated blood from the _________.

The first stage of embryonic development is _____. this process produces _____.

Feedlots are a major cause of _________ in water.

According to the fossil record, plants colonized terrestrial habitats ________.

The behavior of an infant in sensorimotor stage four might best be described as _____.

In amphibians, gases are exchanged through the gills, lungs, and/or _______________. ..

During _________, nucleotide sequence information is changed into amino acid sequence information.

Denaturing gel electrophoresis separates proteins based on differences in _______.

Decomposers are most likely found in the ________.

Control of ______________ is a function of the autonomic nervous system.