Which of the following is true of an amine group? It is the carbon-containing portion of an amino acid.
O It is the unique chemical structure attached to the backbone of each amino acid.
It represents the acid group attached to the central carbon atom.
It is the oxygen-containing portion of an amino acid.
O It is the nitrogen-containing portion of an amino acid.

Metamorphic rocks are formed when sedimentary or igneous rocks are subjected to heat or pressure and recrystallize without melting. which of the following rocks results from the metamorphism of limestone? a. granite b. slate c. sandstone d. marble

Which group of algae is characterized by unicellular organisms and includes some members that would be better classified as zooflagellates? euglenophytes red algae sporozoans green algae

Several bird species feed in a certain species of tree. each bird species feeds in a different part of the tree. which statement is true of these bird species? a. they have adapted to different niches due to competition b. they have a carnivorous relationship with the tree species. c. they have adapted to different niches due to predation d. they have a symbiotic relationship with the tree species.