How does photosynthesis affect all living things?

Which beat describes the brain stem

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.

Lupe is a carrier for color blindness. her husband clifford is colorblind. if lupe and clifford have four children, what's the probability of a boy being colorblind?