Breathing (not everything soz)

• Diaphragm

  A sheet of muscle that forms the floor of the thorax
• Thorax

  Cavity where lungs and heart are found
• Pharynx

  Passage at the back of the mouth (throat)
• Epiglottitis

  Flap of tissue that closes over the trachea when we swallow
• Larynx

  Voice box -contains 2 vocal chords that vibrate to produce sound when air is passed over them
• Trachea/bronchus/bronchiole

  Made up of muscle elastic fibres and C shaped rings of cartilage (prevents collapse)
• Bronchus

  Transports air into lungs
• Cilia

  Trachea, bronchi and bronchioles are lined with mucus secreting cells and tiny hairs called cilia.

  
  

  Mucus traps particles and cilia beat and create an upwards current to move these particles up into the oesophagus where it is swallowed
• Alveoli

  Air sacs at the end of bronchioles
• Characteristics that aid gas exchange in alveoli

  • Thin walls
  • Large surface area
  • Large blood network
  • Moist
• Function of alveoli

  Gas exchange
• Each lung is contained in a pleural membrane
• Gap between lung membranes is called the pleural cavity and is full of liquid which lubricates the membranes to prevent friction of the lung surface during breathing
• Respiration occurs in the

  Mitochondria
• Respiration provide energy
• Cells use up oxygen and produce carbon dioxide and water -released into atmosphere
• Gas exchange occurs by diffusion in the alveoli
• Diffusion

  Movement of molecules from an area of high concentration to an area of low concentration across a semi permeable membrane
• O2 concentration in alveoli is higher than oxygen concentration in the blood
• Plasma

  Liquid part of blood
• Normal blood pH

  7.4
• Part of brain that controls breathing

  Medulla oblongata
• Breathing disorder

  • Asthma

  Symptoms

  • Noisy, wheezy breathing and breathlessness

  Causes

  • Allergens e.g pollen

  Prevention

  • Avoid allergens

  Treatment

  • Use bronchodilator