26. Breathing Flashcards
Label diagram
top to bottom
nose and mouth larynx epiglottis trachea rings of cartilage bronchus bronchiole alveoli lungs ribs diaghram pleural membrane and pleural cavity
Function of nostrils
Filters the air:
Sticky mucus traps dirt and germs
Hairs/cilia trap dirt and germs
warms and moistens air-easier diffusion of oxygen
Function of: Larynx Epiglottis Intercostal muscles Rings of cartilage
Larynx: Produces noise
Epiglottis: Stops air moving down the oesophagus
Intercostal muscles: Contract to move ribcage up and down
Rings of cartilage: Protect trachea
Function of diaghram
a sheet of muscle that moves up and down during breathing
Function of:
- Trachea
- Bronchus
- Bronchiole
- Trachea: brings air in and out of lungs, has cilia and mucus to filter air
- Brings air from trachea to lungs
- Brings air from bronchus to alveoli
Function of alveoli
Little sacs at end of bronchiole where gaseous exchange occurs.
Function of pleural membrane and cavity
Membrane: Surrounds the lungs
Cavity: reduces friction during breathing
Process of inhalation
- Intercostal muscles contract
- Causes ribs to pull up and out
- Diaphragm flattens downwards
- This causes volume of thorax cavity to increase. So air pressure in chest cavity drops. More air is drawn into the lungs and alveoli
Process of Exhalation
- Intercostal muscles relax
- Ribs pull down and in
- Diaphragm pushes upwards
- Causes volume of thorax cavity to decrease. Air pressure in chest cavity rises. Air breathed out
Gaseous exchange
- Oxygen diffuses through the alveolus and capillary linings
- Passes into the RBCs
- O2 diffuses into body cells
- CO2 diffuses from body cell into plasma
- CO2 is diffused into alveoli and is exhaled.
How is oxygen transported
Haemoglobin in RBC
How is CO2 transported
Dissolved in plasma of the blood
By what method are gases exchanged
Diffusion
Adaptations of the lungs and alveoli for gas exchange
Alveoli have large surface area (numerous alveoli)
Large supply of capillaries around alveoli (less distance for O2 to travel)
Alveoli walls 1 cell thick
Alveoli walls are elastic and moist.
What kind of action is breathing?
Automatic: involuntary reflex action
What is the controlling factor of breathing and what part of the body detects this factor
Carbon dioxide Medulla Oblongata (has receptors to detect CO2 concentration)
What happens when CO2 levels increase?
- CO2 levels increase because of increased respiration (exercise)
- CO2 dissolves in the blood
- pH of blood falls (acidic)
- Medulla oblongata detects this change
- It sends an impulse to the intercostal muscles and diaphragm to contract.
- Breathing rate increases to exhale the increased CO2
Name 3 breathing disorders
Asthma Bronchitis Pneumonia TB Emphysema
Asthma symptoms
Wheezing, short of breath, tightness of chest, unable to take in much oxygen, coughing
Asthma causes
Pollen, Dust, Damp air, Certain animals, Chemicals, Smoke, Exercise
Asthma treatment and prevention
Specific drug treatments Steroids Inhaler Bronchodilators Nebulizer Prevention: Identify triggers and avoid or remove
