Volcanic activity files the air w carbon dioxide
It prevents dust from settling on the scope and in the lenses. Also, if working in a lab, a cover can prevent contamination.
The palms of the hands are assumed to be facing forward; arms are at the side.
It is during the process of CELL DIVISION when the cell starts dividing and get converted from unicellular to multi cellular. The cell division can takes place by either mitosis or meiosis.
In mitosis 2 offspring cells are produced from one parent cell while in meiosis 4 offspring are produced from one parent cell.