The answer is C. nitrogen.
Plants are main producers in ecosystems so, primary productivity of ecosystems depends on them. Carbon is necessary for plants, but it is widely present in plants. On the other hand, calcium and sodium are not as essential. However, nitrogen is important for plants because it is necessary to make proteins. Proteins take part in many different processes such as photosynthesis (this is actually primary productivity). But, nitrogen is not available to plants, they cannot absorb it simply from the air but rely on some symbiotic bacteria which are able to.
<span>Activation energy refers to the amount of energy required by certain chemicals for them to have a reaction.
</span>
I think this is an theory changing because a new scientific method was developed. They used what Mendel had learned to test the hypothesis themselves and discovered that he was right.
Answer: The correct option is <span>a long carbon and hydrogen chain and a carboxyl group.
Reason: Fatty acid is basically consists of two main parts:
a hydrocarbon tail connected with carboxylic group as shown in the figure.</span>
The living organism is to make the capability of making your own way of inspiring new ways to inductor the situation on a problem to complete the act on the way of it's respondent to every single thing