This amniotic egg contains the nutrients that the growing embryo needs to develop correctly. Which of the following is an essential element for all living things that is found in the yolk sac?

a. phosphorus

b. chlorine

c. silver

d. radon

The answer to this question is:

a. Phosphorus

This is one of the topmost elements needed by living organisms. It is not a pure element but reactive to anything in contact. When combined with some other elements it serves as necessity of life. It is present in plants or animals in less than 1%.