a) when lactose is absent, the repressor is active, RNA Polymerase cannot bind to the promoter and the structural gene are not formed.
b) when lactose is present, the lac repressor is inactive, RNA Polymerase can bind to the promotor and the structural genes are formed.
Explanation:
The lac operon in E.coli has genes required for lactose metabolism.
It is expressed only when lactose is present in the medium and glucose is absent.
According to the glucose and lactose level the operon is switched on or off.
The lac repressor or allolactose and catabolite activator protein is present in lac operon.
Glucose is the primary source of energy but bacteria loves to fuel down lactose. To use lactose as an energy source lac operon works.
a) when lactose is absent, the repressor is active, RNA Polymerase cannot bind to the promoter and the structural gene are not formed.
b) when lactose is present, the lac repressor is inactive, RNA Polymerase can bind to the promotor and the structural genes are formed.
The lac repressor is a protein that inhibits transcription of lac operon in the absence of lactose.
Answer:
Photosynthesis takes place in the chloroplast (a cell organelle that contains green pigment known as chlorophyll). Chloroplast is found in the cytoplasm of the cell of the plant/tree leaves
I believe the answer would be E because it makes sense
A because this is where the pollen is. so when bugs stand on here they take the pollen somewhere else and by accident they spread it. I hope this helps :}
Answer:
The correct answer is E. Biological.
Explanation:
The biological definition of species states that while two organisms can mate and have successful and fertile breed, then they belong to the same species. Therefore, if there were no genetic flow between both species, it means that mating and breeding were not successful and therefore, they were not the same species.