PATHOLOGY

Detailed explanation-1: -Capillaries, the smallest and most numerous of the blood vessels, form the connection between the vessels that carry blood away from the heart (arteries) and the vessels that return blood to the heart (veins). The primary function of capillaries is the exchange of materials between the blood and tissue cells.

Detailed explanation-2: -Capillaries allow exchange of substances with body tissues through their thin walls. As blood travels at high pressure in the arteries towards the capillaries, pressure filtration occurs which results in plasma passing through the capillary wall into the tissue fluid which surrounds the cell.

Detailed explanation-3: -As blood moves through the capillaries, the oxygen and other nutrients move out into the cells. Then waste matter from the cells goes into the capillaries. As the blood leaves the capillaries, it moves through the veins. Veins merge into larger tubes to carry the blood back to the heart.

Detailed explanation-4: -Capillaries are so small that blood cells can only move through them one at a time. Oxygen and food nutrients pass from these capillaries to the cells. Capillaries are also connected to veins, so wastes from the cells can be transferred to the blood.