Internal Systems

1. Internal Systems THE RESPIRATORY SYSTEM

2. Learning Goals Specific to the RESPIRATORY system: Students Will: • Explain the anatomy of the respiratory system and the process of ventilation and gas exchange from the environment to the cell (e.g., the movement of oxygen from the atmosphere to the cell; the roles of ventilation, hemoglobin, and diffusion in gas exchange) • Begin to understand the relationship between the respiratory system and the circulation system • Be able to describe disorders relating to the respiratory system

3. Why Do We Breath? To Survive! • All aerobic organisms require every cell to obtain oxygen and remove carbon dioxide • This process is known as Gas Exchange! 3 Factors that determine the rate of exchange! Area of Cell membrane Concentration difference- more oxygen in the air than the lungs equals greater rate of diffusion Diffusion distance (slight increases in diffusion distance can greatly reduce diffusion rate)

4. Pathway Through the Respiratory System

5. Composition of the Earths Atmosphere The average Human utilizes about 250 mL of oxygen every minute while resting

6. Breathing Vs. Respiration Breathing: The movement of gases between the respiratory membrane of livings things and their external environment Respiration: The living membrane where the diffusion of oxygen and other gases occurs. Gases are exchanged between the living cells of the body and the external environment

7. Types of Respiration • RESPIRATION EXTERNAL RESPIRATION Involves the exchange of gases (O2 and CO2) between the air and the blood CELLULAR RESPIRATION Involves the production of ATP in the body cells INTERNAL RESPIRATION Involves the exchange of gases (O2 and CO2) between the blood and tissue fluids

8. Simple Gas Exchange All organisms share two characteristics: • Large respiratory surface • Moist environment Single Cell Organisms • Must live in wet, aquatic environments to fulfill the moist requirement • Some simple multi-cellular organisms also exchange gas in this manner (aquatic)

9. Unicellular Organisms On Land • Unicellular organisms like bacteria and fungi also need to exchange gas. • Water in the soil satisfies the moist requirement. • If the terrestrial organism lives on the surface of the soil then the moisture is derived from the soil below and from the air above. • These organisms are severely limited due to these moisture requirements.

10. Specialized Breathing • The larger the organism gets, the more difficult it is to get oxygen to every cell! • INCREASE SURFACE AREA!

11. WORM • Skin Respiration • Skin must be kept moist to allow diffusion of O2 • Skin is lined with capillaries which allow oxygen to enter and carbon dioxide to exit • Circulatory system aids in the process of ensuring all cells respire properly • INSECTS: • Utilize a series of external pores called spiracles which lead to internal series of tubes called tracheae • The tracheae often end in larger air sacs, which supply oxygen to the organs that require it

12. FISH Why can’t fish survive out of water? • Gill Respiration • Unlike worms, fish don’t have their whole body available for gas exchange due to the environment in which they live • Surface area to allow gas exchange is decreased How do fish compensate for this? 1. Surface are where gas exchange takes place is increased 2. A mechanism has evolved to allow the organism to ventilate this surface, that is, to move the oxygen containing medium over the gills to gain fresh oxygen. 3. Countercurrent flow

13. PIG • Tracheal Respiratory System (Internal) • Out of the water (moisture) problem? • Mucus for moisture • Evolved to use tracheal respiratory system and lungs • Breathing is the concept of ventilating a respiratory surface with air and it relies on a simple law of physics: • Air will move from a region of high pressure to a region of lower pressure until equilibrium is acquired

14. The Mammalian Respiratory System • Respiration is made up of four parts • 1. Breathing • 2. External Respiration • 3. Internal Respiration • 4. Cellular Respiration Respiratory Tract • Upper • Lower Nostrils, Pharynx, Glottis, Epiglottis, Larynx, Trachea, Cilia Bronchi, Bronchioles, Alveoli, Lungs

15. Upper Respiratory Tract • Nostrils • Air is passed into he nasal passages where two important things happen! • 1. TURBINATES: Thin bone in nasal passage secretes mucus to moisten air • 2. Many capillaries warm the incoming air • Pharynx • Connects mouth and nasal cavity to larynx and esophagus • Glottis • Opening of trachea • Epiglottis • Prevents food from entering trachea (flap)

16. Upper Respiratory Tract • Larynx • Holds our vocal cords using cartilaginous material • Contain two thin sheets of elastic ligaments called vocal cords, that vibrate when air is forced from lungs to pharynx • Trachea • Windpipe, supported by semi-circular cartilage rings **Most structures in Upper Tract are covered in Mucus**

17. Lower Respiratory Tract TRACHEA R. BRONCHUS L. BRONCHUS Bronchioles Bronchioles Alveoli: Clusters of tiny sacs where gas exchange takes place (External Respiration) Alveoli: Clusters of tiny sacs where gas exchange takes place (External Respiration) LEFT LUNG: 2 Lobes RIGHT LUNG: 3 Lobes

18. Lower Respiratory Tract • At the alveoli: • 70% simple diffusion • 30% facilitated diffusion: by the use of special protein based molecule in the alveoli • Lungs: • Enveloped in tissue called pleura which contains lungs but allows them to expand

19. Mechanics of Breathing Two muscular structures allow ventilation: • Intercostal muscles: surface of rib cage • Diaphragm: muscle that separates thoracic and abdominal cavity These two muscles work in unison to move air in and out of the lungs

20. Mechanics of Breathing Breathing In: • Diaphragm contracts and moves downward • Intercostal muscles contract; rib cage moves upward • AIR MOVES INTO THE LUNGS Breathing Out: • Diaphragm relaxes and moves upward • Intercostal muscles relax; rib cage falls • AIR MOVES OUT OF THE LUNGS

21. Lung Capacity • Tidal Volume • Volume inhaled and exhaled in normal breathing movement • Inspiratory Reserve Volume • Additional volume that can be taken in beyond tidal volume • Expiratory Reserve Volume • Additional volume that can be forced out beyond tidal volume • Vital Capacity • Total volume of gas that can be moved in and out of your lungs • Residual Volume • Amount of gas that remains in the lungs after full exhalation

22. Birds • Migratory birds have evolved and developed a respiratory advantage to give them enough energy to migrate • Utilize air sacs that ensure residual volume is never contact with the lungs • Also have countercurrent exchange system

23. Gas Exchange • Daltons Law of Partial Pressure • This law states that each gas in a mixture exerts its own pressure • The atmospheric pressure at sea level is 101 kPa • Partial pressure of Oxygen • 21% x 101 kPa = 21.21 kPa Atmospheric Pressure of O2: 21.21 kPa Alveoli Pressure of O2: 13.3 kPa Capillary Pressure of O2: 5.3 kPa Where do you think the highest partial pressure of CO2 is?

24. Homeostasis: Maintaining Gas Levels • Chemical receptor helps ensure that CO2 does not accumulate • During exercise, cellular respiration increases • This results in CO2 increases • Our body adapts by increasing breathing movements to flush out excess CO2

25. Disorders Bronchitis • inflammation of the mucous lining in the bronchial tubes resulting in narrowing of the passage way Emphysema • A respiratory disorder that is characterized by over inflammation of the alveoli • Associated with long term bronchitis • Air pressure builds up in the lungs and the alveoli can rupture • This ultimately results in decrease surface area for gas exchange

26. Disorders Asthma Common chronic inflammatory disease of the airways characterized by variable and recurring symptoms • All respiratory disorders decrease oxygen delivery to the issues! • Can we think of any other common ones? • Hypoxia? • Carbon Monoxide Poisoning?

27. VO2max

28. VO2 max is the maximum capacity of an individual's body to transport and utilize oxygen during incremental exercise. • It is also known as aerobic capacity, which reflects the physical fitness of a person.

29. Accurately measuring VO2 max involves fully taxing the aerobic energy system. • Usually involves a graded exercise test on a treadmill in which exercise intensity is progressively increased while measuring ventilation and oxygen and carbon dioxide concentration of the inhaled and exhaled air. • VO2 max is reached when oxygen consumption remains at steady state despite an increase in workload.

30. “Maximal oxygen uptake (VO2max) is widely accepted as the single best measure of cardiovascular fitness and maximal aerobic power.” • http://www.youtube.com/watch?v=O__oZjw8Ljc

31. The average young untrained male will have a VO2 max of approximately 3.5 litres/minute and 45 ml/kg/min. • The average young untrained female will score a VO2 max of approximately 2.0 litres/minute and 38 ml/kg/min.

32. In sports where endurance is an important component, world class athletes typically have high VO2 maximums. • World class male cyclists and cross-country skiers typically exceed 80 ml/kg/min and a rare few may exceed 90 ml/kg/min for men and 70 ml/kg/min for women. 84 ml/kg/min

33. Thoroughbred horses have a VO2 max of around 180 ml/min/kg. • Siberian dogs running in the Iditarod Trail Sled Dog Race sled race have VO2 values as high as 240 ml/min/kg.