Name two things that can be done to ensure that we use ecosystem resources in a sustainable way

The cluster of developing cells from conception until birth is called an

What element is able to combine with itself and hydrogen to form large molecules ?

Amino acids contain the elements carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur. of the 20 amino acids found in humans, 11 are called "nonessential" because they can be manufactured by the body when needed. which elements in these 11 amino acids are commonly obtained from the metabolism of sugar molecules?