What economic system is characterized by an exchange of one product for another
currency
barter
loan
free market

Students in biology are studying the macromolecules of life. they used a calorimeter to determine the calories in various types of food. once the lab was completed, the students ate the left over food samples. monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. elaborate on what happened chemically while chewing the saltine. include the macromolecules present.

What is the key to the recognition of codominance?

_tissues respond quickly to outside stimuli a) epithelia b)nervous c)muscular d)muscular and nervous