Follicle cells in your scalp assemble proteins to build new hair. This most likely involves dehydration synthesis reactions.
Dehydration synthesis forms a peptide bond between amino acids and releases a water molecule. Amino acids connected via peptide bonds form a polypeptide chain, which then chemically interact with other polypeptides in order to create a complex three-dimensional structure of the protein.
True - a homogenous mixtures is a mixture that has the same amount of solute.
It is a cold Artic air mass over Siberia. Air masses are altered because it doesn't stay in one place and changes as it moves due to the temperature of environment that can be caused by moisture. The cold Artic Mass from Siberia will go to the North Pole, Canada then moves further to the South area.