A young boy arranges a shirt on the floor. he

grabs and iron and irons the shirt.

Woman is standing talking to the camera holding a microphone and interviewing voleyball players. Men are standing in a sandy field being interviewed. men

are in sandy field showing he girl how to play beach soccer.

A man is water skiing on a large lake. he

is being pulled by a motor boat.

How to study the chemistry and physiological roles of calcium ions in the body
Understand the difference between the metallic and ionic forms of calcium.
The element calcium follows the trend in properties that is seen with magnesium, sodium and potassium elements. Namely, it is toxic to mammals in its metallic form, while it is benign in its ionic form.
Actually, calcium ions are not only benign but also essential for the metabolism of the body. Study the use of calcium by the body.