What part of the cell controls the amount of nutrients that come in and out of the cell?
the cell shell
the cell wall
the cell membrane
the cell barrier

Idont understand by supporting the plant and holding the leaves up to the light. question 3 options: tap or fibrous root flower petals herbaceous or wood stems leaves with stomata

Describe the response the kidneys have to dehydration and excessive water intake. what happens to the concentration of urine in each case ?

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.