If nearly 79% of atmosphere is nitrogen, how could there be a shortage of nitrogen in some soils? Nitrogen must be converted into nitrates before organisms can use it. If soil lacks nitrogen fixing bacteria, then it has few nitrates for the plants to take in.
the purpose of valves in the heart valves is to allow blood to flow only in one direction. Valves open and close on differential pressure on each side. pulmonary and the aortic valves receive blood from the ventricles and their semilunar valves allow blood to go into the arteries and prevent back flow from the artery to the ventricles.
Answer:
to provide energy, store energy, build macromolecules, and spare protein and fat for other uses
Explanation:
Decomposers include certain types of bacteria, worms, slugs, snails and fungi. All of these organisms break down or eat dead or decomposing organisms to help carry out the process of decomposition.
They are the last step in the food chain, which recycles nutrients and breaks down wastes and organic matter in the ecosystem.