Video and lesson investigations on the topic of muscles and movement. Key concepts include:
- Animal bodies are held in shape by their skeletons.
- Skeletons are made from lots of bones.
- Bones do not bend. Movement in skeletons happens at joints.
- Muscles control movement of joints.
- Muscles can only work by pulling on bones.
- The muscles contract (shorten) as they pull.
- Muscles usually operate as opposing pairs.
- Like machines, our bodies consist of a framework with moving parts.
- Joints are like turning points (or pivots) of levers.
- One muscle, or a set of muscles, contracts and pulls on the bones to cause movement.
- This muscle cannot push the bone back again, but another muscle, or a set of muscles, is used for this.