PE

• Functions of the skeleton

  • Protection of vital organs
  • Structural shape & muscle attachment
  • Formation of joints for movement
  • Blood cell production
  • Store of minerals
• Cranium


  Protects the brain when heading
• Skeleton


  Provides support by providing a structural shape for muscles and tissues to attach

  
• Bones


  Provide anchors for muscles to attach. Tendons attach muscle to bones. Muscles pull on bones to create movement
• Red blood cells


  Carry oxygen
• White blood cells


  Fight infection

  
• Platelets


  Clot blood
• Calcium and Phosphorus


  Stored in the bones to keep them strong
• Types of bones


  • Flat bones
  • Long bones
  • Short bones

  
• Flat bones


  • They are longer than they are wide. They enable gross movements by working as levers
  • They usually protect organs or offer a broad surface for muscles to attach to

  
• Short bones


  • They are as wide as they are long. In sport they allow finer controlled movements
• Structure of a synovial joint

  • Synovial fluid
  • Synovial membrane
  • Articular cartilage
  • Joint capsule
  • Ligament
  • Bursae

  
• Synovial fluid


  Lubricates and reduces friction of the joint, supplies nutrients and removes waste products
• Synovial membrane


  Contains and releases synovial fluid
• Articular cartilage


  Prevent bones from rubbing and acts as a shock absorber
• Joint capsule


  Surrounds the synovial joint, protects and stabilises the joint

  
• Pathway of air into the lungs

  1. Nose and mouth

  2. Trachea

  3. Bronchi

  4. Bronchioles

  5. Alveoli

  
• Trachea


  • Surrounded by rings of cartilage to keep its shape and prevent it collapsing
• Bronchi


  • The passage of air gets smaller and smaller
• Ligament


  Joins bone to bone, helps stabilise the joint
• Bursae


  Fluid filled sacs that provides a cushion between the tendons and bones reducing friction
• Bronchioles


  • Branch out throughout the lungs and carry the air from the bronchi to the alveoli

  
• Alveoli


  • Tiny air sacs where the exchange of oxygen and carbon dioxide occurs
• Structure of the heart

  1. Right atrium contracts (systole) ejecting deoxygenated blood through a valve and into the right ventricle

  2. Right ventricle is relaxed (diastole) and fills with deoxygenated blood

  3. Right ventricle contracts (systole) pushing the deoxygenated blood through valves to the pulmonary artery

  4. Pulmonary artery carries deoxygenated blood away from the heart to the lungs

  5. Blood becomes oxygenated

  6. Vena cava is the main vein bringing the deoxygenated blood back to the heart and into the right atrium

  7. Pulmonary vein transports the oxygenated blood back to the heart and into the left atrium, which fills with oxygenated blood

  8. Left ventricle contracts (systole) pushing the oxygenated blood through valves to the aorta

  9. Left ventricle is relaxed (diastole) and fills with oxygenated blood

  10. Left atrium contracts (systole) ejecting oxygenated blood through a valve and into the left ventricle

  11. Aorta carries oxygenated blood away from the left ventricle to the working muscles the blood then become deoxygenated
• Types of freely movable joints

  • Hinge joint
  • Ball and socket joint
• Features that assist in gas exchange

  • Alveoli have very tiny air sacs with moist thin walls (only one cell thick)
  • Alveoli have a very large surface area
  • Alveoli are surrounded by capillaries
  • It provides a large blood supply

  
• Hinge joint


  Found at the elbow, knee and ankle, allows flexion and extension
• Mechanics of breathing: Inspiration

  Diaphragm and external intercostal muscles contract, external intercostal muscles raise the ribs upwards and outwards, this increases the volume of the chest cavity and causes air to rush into the lungs
• Gaseous exchange


  1. Gases move from areas of high concentration to areas of low concentration

  2. Oxygen is diffused into the blood and binds with haemoglobin

  3. Oxyhaemoglobin is transported to the working muscles

  4. Carbon dioxide is removed from the muscles by haemoglobin
• Mechanics of breathing: Expiration

  Diaphragm and external intercostal muscles relax, internal intercostals contract, this lowers the ribs downwards and inwards, this decreases the volume of the chest cavity and causes the air to be forced out the lungs
• Ball and socket joint


  Found at the hip and shoulder, allows flexion, extension, abduction, adduction, rotation & circumduction
• Vasoconstriction


  The blood vessels constrict to make them smaller. Chemical changes signal the nervous system to constrict blood vessels to inactive areas.
• During inspiration, the pectorals and sternocleidomastoid muscles raise the sternum allowing the lungs to expand further
• Movement possibilities at joints

  • Flexion
  • Extension
  • Abduction
  • Adduction
  • Plantar flexion
  • Dorsi flexion
  • Rotation
  • Circumduction
• Vasodilation


  The blood vessels dilate to make them bigger. Chemical changes signal the nervous system to dilate blood vessels that supply active areas.
• During expiration, the rib cage is pulled down quicker due to the contraction of the abdominal muscles
• Cardiac Output


  Amount of blood leaving the heart per minute
• Flexion


  Bending movement (decreases angle)
• Artery


  • Thick muscular walls
  • Thick elastic walls
  • Small lumen (internal diameter)
  • Carry blood at high pressure
  • Carry blood away from the heart
  • Usually carry oxygenated blood (except the pulmonary artery)
• Stroke Volume


  Amount of blood ejected from the heart per beat