A bone cell, formed when an osteoblast becomes embedded in the matrix it has secreted.
Hydrogen (62.9%), oxygen (almost 24%), carbon (nearly 12%), nitrogen (nearly 0.6%), calcium (0.24%) and phosphorus (0.14%).
Hierarchy - I don’t think I have the full context of the question but the word fits the best of its biology related
Amino acids are acids on one hand, and a base on the other hand.
<h3>What is an acid?</h3>
An acid is a substance that produces hydrogen or hydroxonium ions as the only positively charged ion when it ionizes.
All amino acids have an amine group -
and a carboxylic group -
.
The carboxylic group ionizes such that:

The presence of the amine group enables amino acids to also act as a base.
More on amino acids can be found here: brainly.com/question/14583479
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