A low level of expression of lac operon occur at all tissues. Can you explain the logic behind this phenomenon?

Raghav was returning with his family from a marriage party. On the way, a traffic policeman stopped their car. He asked Raghav’s father who was driving the car to exhale his breath into an instrument to check whether he has drunk or not. After checking from the instrument, he allowed them to go. As a student of chemistry: Can you explain the theory behind this test ?

What is regulation of gene expression? Explain with the help of the lac operon of E.Coli.

Amino acids as the name suggest, have both an amino group and a carboxyl group in their structure.In addition all naturally occuring aminoacids (those which are found in proteins) are called L-aminoacids. From this,can you guess from which compound can the simplest aminoacid be made?

Can you think, for how long would the lac operon be expressed in the presence of lactose?