The concentration of nitrates is often higher in
plant roots than it is in the soil around them.
Plants maintain this difference in concentration
through
(1) active transport (3) excretion
(2) diffusion
(4) coordination

(2) diffusion

Explanation:

Diffusion is a process in which molecules moves from a region of higher concentration to the region of lower concentration. In this condition, plant roots contain high concentration of nitrates than soil so nitrates moves from roots through semi-permeable to the soil by the action of diffusion until the concentration is uniform or equilibrium.

mammal

explanation:

starchy vegetables are high in carbohydrates.

starchy vegetables contain more carbohydrates than non-starchy vegetables.

explanation:

there are two primary categories of carbohydrates, essentially differentiated on the basis of their carbohydrate content (which is in the form of starch - a complex carbohydrate):

those vegetables which contain little amounts of starch are termed as non-starchy vegetables, and some examples include: artichokes, broccoli and bean sprouts.

vegetables high in their starch content are distinguished as starchy vegetables, and some examples include: potatoes, chickpeas and corn.