Bone
From CreationWiki, the encyclopedia of creation science
Bone is made of different types tissues including the outer layer of the bone, the compact middle layer, and the spongy third layer.
Periosteum The periosteum is hard and smooth. It provides protection to the rest of the layers of the bone. It is almost like the "skin" of the bones. The periosteum provides a site for the attachment of muscles, and also contains nerves, blood vessels, and lymphatic vessels.[1]
Compact The compact bone is extremely dense and surrounds the spongy bone. The compact bone also contains many Haversian canals, which also contain nerves and blood vessels. This layer of bone gives the skeleton its strength and allows it to support your bodies mass.[2]
Spongy The spongy bone is where all of the blood cells are created from the bone marrow. Spongy bone contains two different types of bone marrow: red and yellow marrow. The red bone marrow produces red and white blood cells and platelets. The yellow bone marrow, however, is used to store fats.[3]
Broken Bones
Your bones are tough stuff - but even tough stuff can break. Like a wooden pencil, bones will bend under strain. Most fractures occur in the upper extremities: the wrist, the forearm, and above the elbow. Also if the pressure is too much, or too sudden, bones can snap. You can break a bone by falling off a skateboard or crashing down from the monkey bars.
Bones can fracture in a number of different ways. A fracture may be a straight break across the bone (transverse fracture), slanting (oblique fracture) or winding (spiral fracture). The break may run along the shaft of the bone (longitudinal fracture), or the bone may be shattered into pieces (comminuted fracture). Young bone is softer and more able to bend than adult bone, so childrens bones often fracture on one side but bend on the other - known as a greenstick fracture.[4]
There are many different types of fracture, the most common of which is a simple fracture, when a bone breaks cleanly. If you put out your arms when you fall, you could end up with an impacted fracture, where the ends of two bones are forced into one another. A sharp sudden twist of a bone in a game of football could result in a jagged spiral fracture. Road accidents often cause comminuted fractures, where a bone breaks into fragments, or compression fractures, where a bone is crushed.[5]
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