Answer:
It decreases the levels of cAMP in the cell, repressing transcription from the lac operon.
Explanation:
When glucose is absent, cAMP serves as coactivator binds to CRP, the catabolite gene activator protein. The CRP-cAMP complex binds to the site near the lac promoter and stimulates the expression of the operon by RNA polymerase many folds.
Catabolite repression refers to inhibition of the synthesis of enzymes of lactose catabolism when glucose is present as an energy source. In the presence of glucose, synthesis of cAMP is inhibited resulting in its lower cellular concentration. The lower cAMP levels do not allow the binding of cAMP and CRP. The result is reduced expressed of lac operon.
The answers are following
1)a
2)a
3)d
We have been given that different tissue samples are in their respective stage of cell cycle.
Ans is option B because cancerous cells tend to divide indefinitely regardless of the presence or absence of growth factors. In cancerous cells G0 check points fail and the cells are always in some stage of mitosis i.e. cell is supposed to be in any of the following stages of mitosis :
1) Prophase
2) Metaphase
3) Anaphase
4) Telophase
He performed an experiment that explain what occurred on primitive earth billions of years ago. He sent an electrical charge through a flask of chemical solution of methane, ammonia, hydrogen and water. This created organic compounds including amino acids
Hopes this help you.
