This condensation is needed to allow the chromosomes to move along the mitotic spindle without becoming tangled or broken during their distribution to daughter cells. DNA in this highly condensed state can no longer be transcribed, so all RNA synthesis stops during mitosis.
Only the bases varies from one nucleotide to another.
Multicellular is the word you're looking for ;-)
The movement of substances (as by diffusion) across a cell membrane without the expenditure of energy.
