How can plants make their own proteins

I think Plants synthesize protein from the amino acids found in Nitrogen.

Explanation:

Hope it will help you.

Oxygen is the second most abundant element by volume in the ;

The regions of the Earth that has oxygen as the second most abundant element are :

Hydrosphere : This is the region of the earth that is composed mainly of water and oxygen but the major part of the hydrosphere is water while the oxygen is the second most abundant element.

Troposphere : This is the lowest part of the atmosphere which comprises of about 75% of the atmosphere and it contains about 78% Nitrogen and 21% of oxygen.

Hence we can conclude that Oxygen is the second most abundant element by volume in the Hydrosphere and Troposphere.

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