The fact or state of being engrossed within something.
or
the process or action by which one thing that absorbs or it is absorbed by something else.
<span>The gene sequence containing an operator, promoter and repressor is known as an operon. These genes are called as structural genes. the operon is regulated by the presence/absence of the inducer such as glucose/lactose. It may also be a constitutive operon, which works all the time.</span>
Answer:
ciliated and clara cells.
1. A
2. A
3. B
Those are all the answers