1 / 14

Transport of gases in body Respiration ( Breathing )

Transport of gases in body Respiration ( Breathing ). Respiration. = transport of oxygen from air into cells and carbon dioxide from cells to air Ventilation means inhaling air into alveoli and exhaling out of them Gas exchange between air blood  tissues

july
Download Presentation

Transport of gases in body Respiration ( Breathing )

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Transport of gases in body Respiration (Breathing)

  2. Respiration = transport of oxygenfrom air into cells and carbondioxidefromcells to air • Ventilationmeansinhaling air into alveoli and exhaling out of them • Gasexchangebetweenairblood tissues • Cellularrespirationmeansintake of oxygenbycellsfromblood and releasingcarbondioxide into blood

  3. VENTILATION • Active inspiration by inspiration muscles,passive expiration by elasticity of rib cage • In intensive work also exhaling by muscles

  4. Gasexchangebetween air and blood Alveoli • Diameter appr. 0.3 mm • Morethan 300 milj. (→50-100 m2) • Mostdensenetwork of capillaries in body • Gasesaretransportedthrough 0.3 mm thickmembranes • Capillarydiameter appr. 8 mm, contain 100 ml of blood→ a cup of coffee on a tennis field !

  5. Exchange of gases air  blood tissues Atmospheric air: (partialpressure = concentration-% x air pressure) Alveolar air: (air is saturatedwithwater in respiratorytract)

  6. Exchange of gases air  blood tissues P = partial pressure - Gasesalwaysmovefromhigherpartialpressures to lowerthroughalveolar and capillarywalls - Bloodstaysonly 0.4 -0.8 secs, enoughtime for exchange.

  7. Transport of oxygen in body: • 99% of bloodoxygen in Hb and the restdissolved in plasma and redcellfluids • 1 g of redcellHbbinds 1.34 ml oxygen • Oxygensaturation of arterialblood in systemiccirculation is appr. 97 %. • Venousblood appr. 75 % (at rest) • Oxygensaturationdepends on partialpressure of oxygen in plasma (oxyhemoglobindissociationcurve)

  8. HB4 + 4O2  Hb4O8 (worksbothways)

  9. Transport of carbondioxide in body: • - Mostlybound in water (≤ 80%) • CO2 + H2O  H2CO3 • onepart (≤ 20%) bound in Hb (differentsitefromoxygen) • smallpartdissolved (5%)

  10. MB4 + O2  MbO2 (toimii molempiin suuntiin) • Myoglobin: • O2 storage in muscles and heart • protein with iron as Hb • binds one molecule of O2 • releases O2 only after PO2 decreases very low

  11. RESPIRATORY REGULATION • Respiratory center (in medulla)regulatesventilationsothatpartialpressures of O2 and CO2 in alveoli and arterial/venousbloodstayroughlyunchanged

  12. Neuralregulation(informationfromreceptors in muscles,joints and lungs): • Moreimportant in ventilatoryregulationthanhumoralfactors • Powerfulduringexercise • Bothvoluntary and autonomous Humoralregulation(informationfromchemoreceptors): • PCO2, PO2 and hydrogenions (H+) • Mostimportantregulatorymechanism at rest

More Related