Locomotor system

How we move!

Our body moves in response to signals from the brain. These signals travel through the nervous system to our muscles. These contract and relax to allow us to move, hold objects, kick balls and make other movements. The whole system is called the locomotor or musculoskeletal system. It is made up of the skeleton, joints and muscles.

1. The skeleton
The skeleton´s function is:
- to support and give shape to our body and
- to protect the internal organs.

The skeleton is made up of bones and cartilage. Bones are made of hard bone tissue, but cartilage is made of a more flexible tissue.

There are different types of bones:
a. Short and wide bones, such as our vertebrae, provide support and stability.
b. Flat and thin bones, such as our ribs, protect our internal organs.
c. Long and strong bones, such as bones in our arms and legs, are use for movement.

2. Joints

Our bones are connected at the joints by strong, elastic tissue called ligaments. Flexible cartilage protects the ends of these bones.

There are three types of joints:

a. Fixed joints (for example the skull  that does not move)

b. Semi-flexible joints (vertebrae which allow some movement) 

c. Flexible joints (elbows, wrists, knees, ankles and shoulders which allow a lot of movement).