If 21% of a dna strand is composed of adenine bases, what percent of the strand is composed of guanine bases?

What role do traits play in affecting an organisms ability to reproduce? finches

The pharynx is the structure in the body that serves as a pathway of both air and food. how does the body make sure that food does not get into the lungs? the salivary glands secrete enzymes that pull food out of the air pathway. the small intestine pushes the air out of the digestive system. the pancreas breaks down food in the air pathway. the epiglottis closes the air pathway so that food will not enter it.

The cluster of developing cells from conception until birth is called an