ocr gcse pe

• Functions of the skeleton

  • Support
  • Posture
  • Protection
  • Movement
  • Blood cell production
  • Mineral storage
• Support

  • Provides a framework for muscles to work against
  • Supports the body in an upright posture
• Posture


  • Correct shape and position of the body for specific sports and activities
• Protection

  • Protects internal organs, soft tissues and vital organs like the brain, heart, lungs and reproductive organs
• Movement


  • Provides a surface for muscles to attach and create a system of levers to enable movement at joints
• Blood cell production

  • Produces red blood cells to carry oxygen and carbon dioxide, and white blood cells for the immune system
  • Also produces platelets to help blood clotting
• Mineral storage


  • Stores and releases minerals like calcium and phosphorus that are important for bone health and muscle contraction
• Application of skeleton functions

  • Supporting the lower body when a rugby forward lands on their feet after a line out
  • Posture allowing a tackler to create the correct shape and wrap their arms with the correct technique
  • Protection of the sternum protecting the heart when players collide during a tackle
  • Movement using leverage at the elbow joint when a rugby player passes the ball
  • Red blood cells carrying oxygen and carbon dioxide for aerobic respiration in the leg muscles during running
  • Mineral storage of calcium making leg bones dense and strong to cope with the weight bearing of rugby
• Agonist muscle


  Muscle that produces the movement, the prime mover
• Antagonist muscle


  Muscle that relaxes to allow the agonist to contract and produce the movement
• Fixator/stabiliser muscle


  Muscle that stabilises the joint above the one moving, to make the movement more efficient
• Muscle actions

  • Bicep as agonist, tricep as antagonist during a bicep curl
  • Deltoid as fixator/stabiliser during a bicep curl
  • Tricep as agonist, bicep as antagonist during a press-up
• Agonist

  Muscle that contracts to produce a movement
• Antagonist

  Muscle that lengthens and relaxes to allow a movement to occur
• Agonist and antagonist muscles work in unison and in combination, they cannot work alone
• Muscle groups

  • Quadriceps
  • Hamstrings
• Knee extension

  1. Quadriceps contract

  2. Hamstrings relax
• Lever

  • Requires a rigid bar, fulcrum, load/resistance, and effort (muscle contraction)
• First class lever


  Fulcrum is between the load and the effort
• Second class lever

  Load is between the fulcrum and the effort
• Third class lever


  Effort is between the fulcrum and the load
• Mechanical advantage


  When a lever overcomes a large load with relatively little effort
• Mechanical advantage is found in second class levers
• Mechanical advantage creates a short range of motion and is slower, but more powerful</b>
• Sagittal plane

  Movement along this plane includes bicep curls, jumps, throwing actions, forward rolls
• Frontal plane


  Movement along this plane includes shoulder abduction, leg abduction/adduction
• Transverse plane


  Movement along this plane includes rotation, such as a discus throw
• Longitudinal axis


  Rotation around this axis includes 360 degree twists, pivoting
• Transverse axis


  Rotation around this axis includes somersaults, flexion/extension
• Frontal axis


  Rotation around this axis includes cartwheels, diving saves
• Blood returns to the heart via the vena cava vein
• Pathway of blood

  1. Red blood cell returns to heart via vena cava vein

  2. Enters right atrium

  3. Passes through tricuspid valve to right ventricle

  4. Pumped out through pulmonary valve into pulmonary artery

  5. Travels to lungs for oxygenation

  6. Returns to left atrium via pulmonary vein

  7. Passes through bicuspid valve to left ventricle

  8. Pumped out through aortic valve into aorta

  9. Distributed to body tissues

  10. Returns to vena cava
• Pulmonary circuit


  Loop from right ventricle to lungs and back to left atrium
• Systemic circuit


  Loop from left ventricle to body tissues and back to right atrium
• Heart valves

  • Tricuspid valve
  • Pulmonary valve
  • Bicuspid valve
  • Aortic valve
• Red blood cell


  • Lacks nucleus
  • Contains hemoglobin
  • Transports oxygen and carbon dioxide
• Oxyhemoglobin


  Hemoglobin combined with oxygen
• Alveolus


  Site of gas exchange in the lungs
• Gas exchange in alveoli

  1. Carbon dioxide diffuses from blood into alveoli

  2. Oxygen diffuses from alveoli into blood
• Factors that facilitate gas exchange in alveoli: