Relationship between vitamin b12,b6 deficiency and homocystinuria

The trp operon in e.coli regulates genes that code for enzymes required for synthesis of the repressible operon. when tryptophan is not available amino acid tryptophan. the trp operon is a in the environment, the trp repressor protein activeinactiveregulated. therefore, rna polymerase can bind to the genes to begin transcription.

Hurry where is the majority of earth's water found? o glaciers o oceans ground o rivers and lakes

What function does the limb sever in each animal? how are the limb bones of the four animals similar? based on these similarities what can be inferred about the evolution of the four animals.