anatomy
Functions of the Skeleton
Support the body
Protect vital organs
Help the body to move
make red and white blood cells
What are internal organs protected by?
Internal Organ | Protected by… |
Heart | Ribcage |
Brains | Skull |
Lungs | Ribcage |
Spinal Cord | Spine |
Reproductive Organs | Pelvis |
Broken Bones
A broken bone is called a fracture, you can view this by taking an x-ray. The different types of fracture are:
greenstick: bone is not completely broken
simple: completely broken
compound: when the bone breaks through the skin
Ossification
ossification: formation of bone from cartilage
In humans, the skeleton starts off as cartilage. The cartilage is slowly replaced by minerals (which eventually turns to bone). As the cartilage is replaced, it gets harder and stronger. You can determine if someone has stopped growing by looking at the amount of cartilage left in their body..
Joints
The skeleton is made up of bones which meet at joints. There are several types:
ball and socket joint: the widest range of movement which allows the joint to rotate in 360 degrees, for a lot of flexibility, for example the shoulder and hips. Both the ball and socket are covered by a layer of cartilage.
hinge joint: work like a lever, and allow a movement of 180 degrees, where muscles work in pairs to contract and relax to move the joint for example the elbow and knee.
fixed joint: fixed/fused joints form between two or more bits of bone and they do not move, grow, or get smaller. once seperate bones fuse to form a solid skull in early years.
Ligaments
Ligaments connect bone to bone. They allow the joint to move where it needs to, but keeps the bones aligned. Ligaments are elastic and stretchy to prevent snapping when joints are bent.
Tendons
Tendons connect muscle to bone. They have to be very tough and strong to hold powerful muscles to strong bones. This allows the muscles to pull up on a bone. Tendons cannot be stretchy because muscles contracting would caiss the tendon to stretch and the joint would not move.
Cartilage
Cartilage is a strong and spongy tissue. It forms round the end of ball and socket, hinge and pivot joints to protect the end of the bone. It reduces friction to protect our bones. Arthritis is when cartilage wears down and the end of bones in a joint grind together when it is moved.