Muscle Facts: What Are They?
The human body consists of three main parts: the skeleton, organs (besides heart and lungs), and muscles. Bones are made up of cells called osteocytes which make up bone tissue; these cells are connected to each other through long fibers called myofibers. These fibers provide support for bones while allowing them to move around freely. Osteoblasts produce new bone cells, which then become cartilage and eventually bone. Bone cells are specialized to form different types of bones: cartilages (short for carpal), phalanges (for fingers), metacarpals (for hands) and phalanxes (for feet).
Bones have many functions including supporting the weight of the body, forming strong joints and even acting as shock absorbers when walking or running. The skeletal system is made up of several layers, all of which work together to keep the body stable.
The skeleton is composed mainly of cartilage and fat. Cartilage is a tough connective tissue that provides structure and supports muscles. Fat helps regulate body temperature, regulates blood pressure, aids digestion and acts as insulation from cold temperatures.
Together they give us our soft bodies!
Bone Structure & Function: Why Do We Need Bones?
Besides providing structural support, bones help maintain body shape and provide a place for blood to produce red blood cells. Red blood cells carry oxygen from the lungs to the rest of the body. They also fight infection, repair damaged tissue, produce hormones, and store minerals.
Bones are made up of living cells that are constantly regenerating. This regeneration takes place in the bone marrow, which is full of nerve cells, blood and lymphatic vessels, and bone tissue.
Benefits of Being a Bone
In addition to being a place for making red blood cells, bones also play an important role in protecting our vital organs. The skeleton also helps us move around and get around by providing protection for our internal organs and muscles. The spine also helps protect the spinal cord which is the part of the nervous system that sends messages to all parts of our body.
How Does a bone form?
Osteoblast, or bone-forming cells produce a protein that hardens into minerals, which make up bone cells. The process of cells becoming hard and solid is called ossification.
How long does it take for a bone cell to turn into a solid mineral?
Typically it takes about 10-12 weeks.
How Old Are Your Bones?
Are you curious to know how old your bones are?
Just count the rings! Our bones grow new layers every year, and if you cut a bone in half you can see these rings. Our tooth enamel is made up of many layers too. You can even count these layers to know how old your teeth are!
The Vertebral Column: How Do We Move Around?
The vertebral column or backbone is part of the skeletal system. It is made up of 33 bones called vertebrae and it protects the spinal cord. The spinal cord is part of the central nervous system and it carries messages from the brain to the rest of the body and vice versa.
The first few vertebrae protect the spinal cord from injuries. They have hard plates of bone called vertebral laminae that protect the spinal cord. Injuries to this area can be fatal.
The first two parts of the vertebrae are called the cervical or neck part and they protect the nerves that go to the head and arms. There are seven cervical bones. Our next set, located in the chest area, is called the thoracic or chest part.
The last 12 vertebrae are called the lumbar part or lower back and they protect our internal organs in the lower part of our body.
If you want to count your vertebrae, start at the top of your neck and feel along your back.
Do you feel little bones?
If so, you have a vertebral column!
The Skull: Protecting Our Brain
The skull is the first protective barrier for your brain. It has holes in it called “foramina” and these are holes that contain blood vessels, nerves and sometimes even muscles that let the muscles move our jaw and chewing.
The cranium or outer part of the skull has two holes in it: the auditory meatus or ear hole and the eye orbit or eye hole. These holes are important so we can see and hear.
The Skull Has Several Parts
The cranium or the outer part of the skull has several parts. They include: the frontal, the parietal, the temporal, the occipital, and the nasal. The parietal, occipital and nasal are flat bones while the frontal and temporal bones are curved.
If you were to cut open your head, you’d see these bones.
The skull stays open at the sutures or joints. The joints between the bones are covered with a thick material called “malleus” or “mall” in layman’s terms. This is important so the bones can move and let you turn your head from side to side.
While normal head movements are not harmful, if you were to severely twist or bend your neck, this could put pressure on the spinal cord and could be quite painful.
The Face: It’s More than Just a Hole for Air
The face is a very important part of our body. It is the first thing people look at. The face includes the eyes, ears, nose and mouth.
Let’s begin with the ears and work our way to the front.
The ear has three parts: the outer ear, the middle ear and the inner ear.
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