Answer:
The lactose present prevents the production of lactase
Explanation:
This question is describing a set of genes in bacteria called LAC OPERON. Lac operon controls the production of lactase, which is the enzyme that digests lactose. However, this gene can be regulated at the transcription level i.e caused to be transcribed or not depending on certain factors.
According to the question, lac operon, which regulates the production of enzymes will be transcribed and subsequently translated i.e. turned on when there is a substrate (lactose) that the produced enzyme will work on. However, when there is no need of the lactase enzyme or there is absence of lactose (substrate), the lac operon gene is turned off.
Note that, the statement that "The presence of lactose prevents the production of lactase" is not correct.
Explanation:
plants > herbivorous insects > predaceous insects > toads.
Answer:
option B) is correct
Explanation:
The all or none response means that if a muscle contracts, it will contract completely. Thus implying the all or none law which states:
The potential of a response of a muscle fiber or nerve cell is independent of the potential of the stimulus. If a stimulus is more than a certain critical value it will trigger muscle fiber or a nerve. Most importantly resulting in either an all-or-none response thus reducing possibility of any information loss.
It is most likely due to the fact that the attenuation is the evolutionary relic, which by accident has remained does not support the actual reason of the dual control to regulate the operon.
Answer: Option E
<u>Explanation:</u>
In bacteria transcription and translation carries out at the same time so or the termination of transcription in premature phase in bacteria uses a special mechanism which is called as attenuation T.
he attenuation in bacteria is a regulatory mechanism. Trp operon is the group of codes of the components. These operons are the actual functioning group of the DNA.