(159 g Ca/1) x (1 mol Ca/40.07 g Ca) x (6.02*10^23 atoms Ca/1 mol Ca)
= 2.39*10^24 atoms Ca.
Because their valence shell have stable electrons so they can't gain or loose electrons.
in ionic bonds the elements should gain or loose electrons
DNA extraction from living cell
DNA is present inside nucleus surrounded by nuclear membrane. then cell is surrounded by plasma membrane, it means that DNA inside living cell is enclosed in two layers.
Removal of cell membrane
In order to remove cell membrane some detergents are applied followed by physical lysis through vertex.when the first cell membrane is pierced it is removed through centifugation by adding phenol and chloroform.
Removal of nuclear membrane
Proteinase enzyme is added which help in rupturing of nuclear membrane and removal of histone protein from DNA. Then RNAse is added to remove RNA from DNA.
This is true because if you put the tennis ball in boiling water, oxygen molecules in the ball will move more vigorously, thus the dent will disappear.
