The organization of our skeleton and muscles is a wonder of natural engineering. Few people ever question why our bones are in the core of our limbs, surrounded by soft tissue such as muscles, tendons and skin. But could it be the other way around?
Insects and other invertebrates have shells and hard skins called exoskeletons, but they restrict the size to which these animals can grow. Our system, with the bone inside, obeys certain principles of engineering that humans have learned to use in large structures, such as suspension bridges and sailing boats.
In these structures the compression forces act on a single supporting element that holds the weight through a series of more or less flexible ropes (the steel cables in suspension bridges and ropes in sailing boats), which are under constant tension.
This distribution of tasks - much like the tasks undertaken by our bones and joints - results in great strength and flexibility, and a relatively low overall weight.
Early Days
In the embryo, the first signs of the skeleton appear as cartilage buds around the fourth week of development, already in a position compatible with the limbs they will originate. This cartilage is a semi rigid structure like those we have in our ear lobes and at the tip of our noses. However, by the ninth week, blood vessels from the surrounding tissue penetrate the cartilage and start the process that will convert these buds into real bone.
These blood vessels penetrate the buds through their mid portions, and areas of a special calcified tissue start to appear, replacing the cartilage. Later on, other vessels penetrate the edges of the bones, close to the joints and form other centers of calcification. These centers of calcification grow continually and eventually get very close to each other, leaving only discs of cartilage that will continue to grow and will be responsible for our growth in height until the end of adolescence.
The cartilage in the tips of the bones forms an important cushioning system for our joints, which will allow for lubrication and good movement. Unlike bone, cartilage will never be replaced. Cartilage tissue has a poor capacity to recover from trauma and wear; later in life, as a result of wear and tear, thinning and loss of this cartilage may lead to a condition generally known as osteoarthritis.
Wendy works as a women's health consultant has always been keen on protecting and promoting her health, especially when she started to look for hot flash remedies due to early menopause symptoms. Here she talks about how to protect your bones during menopause with natural herbs for menopause and natural hormone replacement therapy.
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