Question

1. Mass movement of water along pressure gradients is known as ­­­bulk flow. Describe how capillary action helps/hurts this concept.

Answer 1

BULK FLOW-

movement of fluids down a pressure or temperature gradient .

it is used by small lipid insoluble solutes that are present in water to cross cappillary wall.

CAPILLARY ACTION :

ability of a liquid to flow in narrow spaces without assistance or without oppostion of external forces.

it occurs because of intermolecular forces between liquid and surrounding solid surface ..

CAPILLARY ACTION HELPS THIS CONCEPT AS :

IN PLANTS :capillary acion is seen in plants .water is brought high in trees by branching ,evaporation creating depressurization ,osmotic pressure added to roots .

in plants cohesion -adhesion theory -water transport in xylem relies upon cohesion of water molecles to each other and adhesion(capillary action)to vessel wall by hydrogen bond combined to high water pressure to plant substratum and low pressure of extreme parts e.g leaves

IN ANIMALS:capillary action for water intake is described in animals such as ligia exotica .

in animals blood circulation is an e.g of capillary example