Muscles and movement

Pull, antagonistic action

Where muscles work in pairs so that when one relaxes, the other contracts and pulls the bone allowing us to move our bones.

• Contracts/ relaxes slowly
• Doesn't get tired
• e.g. lines the intestines, blood vessels, in the airways of the lungs

• They cause movement a the joints
• attached to bones by tendons
• made of long fibres of many cells that have fused together
• Contract quickly but soon get tired
• eg calfs, arms

• Has branching fibres
• this muscle keeps the heart beating
• never gets tired