Usually when scientist wants to test whether one compound or one phenotype is related to another phenotype. Then they need to control this variable when conducting experiments.
Answer:
an inducer
Explanation:
An Enzyme is a protein molecule found in cells which work as biological catalysts.
They speed up chemical reactions in the body, but do not get used up in the process, and can be used over and over again.
In chemistry inducers are molecules that regulates gene expression, and can bind to protein repressors or activators.
Lactose here acts as an inducer because it inactivates the repressor of an operon.
Molality= mol/ Kg
if we assume that we have 1 kg of water, we have 3.19 moles of solute.
the formula for mole fraction --> mole fraction= mol of solule/ mol of solution
1) if we have 1 kg of water which is same as 1000 grams of water.
2) we need to convert grams to moles using the molar mass of water
molar mass of H₂O= (2 x 1.01) + 16.0 = 18.02 g/mol
1000 g (1 mol/ 18.02 grams)= 55.5 mol
3) mole of solution= 55.5 moles + 3.19 moles= 58.7 moles of solution
4) mole fraction= 3.19 / 58.7= 0.0543