1. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise A guide to respiratory fitness THE RESPIRATORY SYSTEM main listing enterquit © Copyright Ali Clarke Design 2003

2. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Contents - Respiratory Introduction Structure of the respiratory system Breathing Lung function Lung capacity Summary main listing quit

3. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise

4. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise

5. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Introduction  what is the respiratory system  function of the respiratory system

6. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise The respiratory system is made up from the following components; What is the respiratory system?  Lungs  Airways  Blood supply  Respiratory muscles

7. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Function of the respiratory system  To remove the waste gas carbon dioxide from the body  To get air into the body so oxygen can be added to the blood

8. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise The respiratory system

9. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Structure of the Respiratory System  upper airways  lower airways  structure of the airways  lungs  blood vessels  respiratory muscles

10. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Respiratory – move air in/out of the airways & lungs muscles  The respiratory system is made up from several components Structure of the respiratory system Airways – allow oxygen into the body Lungs – deliver oxygen to the bloodstream Blood vessels – deliver oxygen to the body tissues

11. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise The upper airways  The airways are divided into upper & lower  The upper airways begin in the nose/throat region, or nasopharynx  Inhaled air travels down through the ‘voice-box’ (or larynx ) before entering the ‘windpipe’, also called the trachea  The trachea then divides into the right & left main bronchus, supplying air to each lung

12. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise The lower airways  Each main bronchus splits into increasingly smaller branches, called bronchioles, that reach every part of the lung tissue  The bronchioles finally divide into tiny sacs, called alveoli, where the exchange of oxygen (O 2 ) for waste carbon dioxide (CO 2 ) in the blood takes place  There are more than 300 million alveoli in each lung, providing a huge total surface area for oxygenation to take place (equivalent the to area of a tennis court!)

13. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Structure of the airways Lower airways nasal cavity Upper airways nasopharynx epiglottis trachea oesophagus larynx

14. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  The lungs are the organs that allow us to breathe  Each lung is joined to a main bronchus, which is then attached to the trachea (windpipe)  The lungs are surrounded by a thin membrane called the pleura  Each lung is divided into regions called lobes  The lungs have a soft, spongy texture that allows them to stretch as we take a breath  The inside of the lung contains numerous airways that divide many times to resemble the branches of a tree The lungs

15. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Structure of a lung Alveolar sacs Lungs Windpipe (Trachea) Lung tissue Bronchus Bronchiole Pleural membrane

16. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  Lung tissue has a very rich blood supply  This allows as much blood as possible to pass through the alveoli (air sacs) for oxygenation  The oxygenated blood travels to the heart to be pumped to the body tissues  Deoxygenated blood containing waste CO 2 travels to the heart & is then pumped back to the lungs for more O 2 to be added (& so on…)  This movement of blood between the heart & lungs is called the pulmonary circulation Blood vessels

17. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Blood vessels Pulmonary circulation Lung Capillaries Left heart To Body From Body Right heart Blood vessels in the lung Pulmonary Vein Pulmonary Artery

18. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  Various muscles are required to contract & relax in order to move air in & out of the lungs Respiratory muscles Intercostal Muscles Diaphragm  These are called the ‘respiratory muscles’ and include the

19. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Respiratory muscles  Diaphragm  A large, dome-shaped muscle that divides the chest from the abdomen  The base of each lung is attached to it  It contracts & flattens, pulling the lungs down to expand them & opening the chest  Intercostal muscles  Lie between the ribs  They contract to pull the ribs up & out, opening up the chest & expanding the lungs

20. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Respiratory muscles Diaphragm Larynx Trachea Lung Sternum Nasopharynx Diaphragm Intercostal muscles Intercostals (shaded)

21. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Breathing  how oxygen gets in  how carbon dioxide is removed  mechanisms for breathing

22. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  The air we breathe passes through the upper airways first; nasopharynx, larynx, trachea & main bronchi  It then enters the lower airways of the lungs; small bronchi & bronchioles  Finally, the air enters the many tiny air sacs, or alveoli How does oxygen get in?

23. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  The alveoli are covered with microscopic, thin-walled blood vessels, called capillaries  O 2 from the air is taken up into the blood within these capillaries, it then flows into the larger blood vessels & eventually ends up in the heart  Oxygenated blood is pumped out of the heart & into the blood vessels supplying the body’s tissues  Upon reaching the tissues, the O 2 is released & the blood is said to be deoxygenated How does oxygen get to the tissues?

24. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  Waste CO 2 produced by the cells is collected in the blood & travels back to the heart via the circulation  This deoxygenated blood is pumped from the heart into the blood vessels of the lung, eventually arriving in the capillaries  The capillaries lining the alveoli release CO 2 into the air sacs, it then travels up the airways & out of the body into the atmosphere How is carbon dioxide removed?

25. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  This increase in chest volume makes the pressure inside the body lower than that outside the body  To move air into the lungs, the volume of the chest must be made to increase by contracting the respiratory muscles; Intercostals – pull ribs up & out Diaphragm – flattens downward, stretching lungs  This causes air to be sucked down the airways & into the lungs How do we breathe in?

26. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Mechanism of breathing in contracting Diaphragm (Inspiration) inspiration Intercostals (Inspiration)

27. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise How do we breathe out?  Moving air out of the lungs involves reducing chest volume by relaxing the respiratory muscles; Intercostals – ribs move in & down Diaphragm – pushes upwards  This decrease in chest volume makes the pressure inside the body higher than that outside  This causes air to be squeezed out of the lungs & up into the airways

28. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Mechanism of breathing out Diaphragm (Expiration) expiration relaxing Intercostals (Expiration)

29. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Lung Function  gaseous exchange  respiration

30. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  This is the addition of oxygen to the blood & the removal of waste carbon dioxide from it; i.e. it is the ‘exchange’ of one gas (CO 2 ) for another (O 2 )  Gaseous exchange takes place in the air sacs of the lung, called the alveoli  The lining of each alveolus is very thin & is covered by a network of tiny blood vessels, called capillaries  O 2 from inhaled air travels across the alveolar lining & enters the capillaries  Here, it is taken up by red blood cells in a special oxygen- carrying molecule called haemoglobin Gaseous exchange: O 2

31. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  Waste CO 2 must also be removed from the body  CO 2 is released from the cells & taken up by the tissue capillaries, where it dissolves into the blood  CO 2 is then carried in the blood vessels until it eventually reaches the capillaries that line the lung alveoli  CO 2 travels out of the capillaries & across the alveolar lining to enter the ‘airway tree’  CO 2 is then pushed out of the body during expiration Gaseous exchange: CO 2

32. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  This is the process whereby cells breakdown O 2 & nutrient (sugar) to release energy  CO 2 is formed as a waste product during this process  Respiration can be expressed in this simplified equation: Cellular respiration O 2 + sugar  (oxygen) (water) (carbon dioxide) + CO 2 + H 2 0 energy

33. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Lung Capacity  lung capacity  lung capacity & fitness  effects of exercise  effects of smoking

34. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  The amount of air breathed in/out during normal breathing is called the tidal volume  The largest amount of air that can be forced out of the lungs after taking as big a breath in as possible is called the vital capacity  The amount of air left behind is called the residual volume  Lung function is measured using a peak flow meter or a more complex machine called a spirometer Lung capacity

35. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Lung capacity normal breathsmaximum exhalation Tidal volume Residual volume Vital capacity Total lung capacity

36. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  Lung capacity varies with age, sex, body shape, & level of fitness  ‘Lung capacity’ is not the same as ‘respiratory fitness’  Respiratory fitness is determined by measuring the maximum amount of O 2 that can be used by a person’s body, this is called VO 2max  The higher VO 2max the fitter the individual Lung capacity & fitness

37. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  The respiratory system responds to the demands of exercise  More O 2 is required by the muscles & more CO 2 is produced for removal  Breathing rate increases  Depth of breathing increases (maximum = vital capacity)  Blood flow through lungs increases Effect of exercise

38. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Exercise  Exercise keeps the lungs in good condition  Gives your heart & lungs a good workout  Promotes a healthy lifestyle  Improves your quality of life

39. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise  Smoking damages your lungs  Reduces the amount of O 2 that can be carried in the blood  Damages the lining of the airways & increases the amount of mucus produced  Reduces alveolar function  Increases the risk of lung infection, emphysema, bronchitis, asthma, & lung cancer Effect of smoking

40. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Smoking & fitness  Smoking damages your fitness  Reduces lung vital capacity  Reduces aerobic fitness

41. backcontentsnext cardiovascularrespiratorymusculo-skeletaldiet & healtheffect of exercise Respiratory system: summary  Respiratory system = lungs + airways + blood supply + muscles  Exercise keeps the respiratory system healthy  Exercise improves respiratory fitness  Adds O 2 to blood & removes CO 2 from it backcontents end