The center of the dna molecule, the rungs of the ladder, are composed of
a. phosphates only.
b. nitrogenous bases only.
c. phosphates and sugars.
d. nitrogenous bases and sugars.

Wht happens as electrons in the electron transport chain release their energy

In what for do plants utilize nitrogen? why do they need nitrogen?

Which of the following is a difference between active transport and facilitated diffusion? view available hint(s)which of the following is a difference between active transport and facilitated diffusion? facilitated diffusion can move solutes against a concentration gradient, and active transport cannot.active transport involves transport proteins, and facilitated diffusion does not.facilitated diffusion involves transport proteins, and active transport does not.active transport requires the expenditure of cellular energy, and facilitated diffusion does not.