1. A student looks at a cell under a microscope. Which of the following observations would indicate that the cell is from a plant rather than an animal? A.

a nucleus located inside of the cell

B.

numerous cilia on the outside of the cell

C.

chloroplasts in the cytoplasm of the cell

D.

a thin membrane around the edge of the cell

d. organisms have cells with different shapes and functions.

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.