The mutation resulting in sickle cell disease changes one base pair of DNA so that a codon now codes for a different amino acid, making it an example of a missense mutation. Missense mutation is the mutation characterized with <span>changes in one base pair so that the whole amino acid is changed.</span>
DNA replication begins when something called Helicase (an enzyme) unwinds the helix structure of the DNA. It does this so that Primase can then come along and set down an RNA primer.
TRNA and mRNA i would say
Cold air creates high pressure low pressure is created by hot/warm air La Nina creates cooler temperature then el nino