Osteoclasts resorb both the mineral and the organic phases of bone. They are giant, multinucleated cells containing from two to several hundred nuclei. Transmission electron micrographs show osteoclasts to have several distinctive features. One of the distinguishing features is the ruffled border, which is located at the interface between the resorbing bone surface and the cell surface within resorption lacunae. Secondly, the cell surface next to bone is characterized by close apposition of the plasma membrane to bone and an adjacent, organelle-free area, rich in actin filaments, called the clear zone.4 The clear zone encircles the ruffled border completely so that the site of resorption is isolated and localized. Osteoclasts are richly endowed with lysosomal enzymes with one such enzyme, tartrate-resistant acid phosphatase (TRAP), being relatively specific to the osteoclast. Osteoclasts also contain carbonic anhydrase, which is utilized for the production of H + ions secreted at the ruffled border.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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