What do you mean by desertification???

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Which best example best demonstrates the importance of having knowledge of evolutionary relationships? a. illustration of a plant b. organ transplantation between species c. blood donation from a human d. do you need sequence of an insect.

Which number represents a basic ph, 4 or 9? numerical answers expected! answer for blank 1: i'll give

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.