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.
The appropriate answer is a. the conversion of radiant energy to chemical energy. Plants use light from the sun to convert carbon dioxide and water to glucose. An important bi-product of this reaction is oxygen which is vital to all life on earth. When humans consume glucose and do work they are converting chemical energy into heat energy and mechanical energy.
The water, warmed by the sun, turns into vapor (evaporates), and passes out through thousands of tiny pores (stomata) mostly on the underside of the leaf surface. This is transpiration. It has two main functions: cooling the plant and pumping water and minerals to the leaves for photosynthesis.
James Watson and Francis Crick
