Why is it important for nitrogen to be able to cycle through an ecosystem? A. Organisms use it to build proteins and carbohydrates.
B. Organisms use it to build lipids and nucleic acids.
C. Organisms use it to build proteins and nucleic acids.
D. Organisms use it to build carbohydrates and lipids.

the answer is c

explanation:

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.

yes we can.   a lady urinates from her urethra.