I'm new here and this is one of the first things i've done on this site but to answer the question, i believe the answer is amino acids
Bacteria reproduces exponentially so like at first you’d have one, then 2, then 4, then 16... (because each bacteria splits into 2) and eventually a few hours later you’ll have millions
Mutations are spontaneous and occur at random however there are some mutagenic agents which increase the chance of this happening such as radiation exposure. If it is a point shift mutation then only a few bases on the dna sequence are changed so only changes a few of the amino acids in that chain (such as inversion of a base). If its a frame shift then the base sequence is altered so much so that every amino acid from after that changes (such as deletion of a base) which can create things such as cri-du-chat syndrome which results from a piece of chromosome 5 is missing. Hope this helps:)
