Answer:
Both a torch and a star are considered to be luminous objects. In order for us to see an object that is non-luminous, it must reflect some of the light it receives from a luminous source, such as the Sun.
Explanation:
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.
This is gravity.
Gravity is a force that is exerted on all objects on earth. The greater the mass, the greater the force of gravity is on an object.
Answer:
If you place an animal or a plant cell in a hypertonic solution, the cell shrinks, because it loses water ( water moves from a higher concentration inside the cell to a lower concentration outside ). A single animal cell ( like a red blood cell) placed in a hypotonic solution will fill up with water and then burst.