Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
7 Cards in this Set
- Front
- Back
|
How is carbon dioxide transported? |
1/ 5% dissolved directly in plasma 2/ 10% combined w/haemoglobin to form carbaminohaemoglobin 3/ 85% transported in form of hydrogencarbonate ions |
|
|
How are hydrogencarbonate ions formed? |
1. CO2 diffuses into blood; some enters RBCs 2. CO2 combined w/water to form weak acid called carbonic acid 3. This reaction is catalysed by enzyme carbonic anhydrase 4. Co2 +H2o -> H2CO2 5. Carbonic acid dissociates to release hydrogen ions (H+) and hydrogencarbonate ions |
|
|
What is the chloride shift? |
When hydrogencarbonate ions diffuse out of RBCs - charge inside RBC is maintained by movement of chloride ions from plasma |
|
|
What effect do hydrogen ions have on the contents of a RBC? |
The contents become very acidic to prevent this- hydrogen ions = taken up by haemoglobin to produce haemoglobinic acid Haemoglobin is acting as buffer |
|
|
How is oxygen released? |
Partial pressure of respiring tissues is lower than in lungs -bc its been used for respiration Thus oxyhaemoglobin dissociates and releases oxygen into tissues |
|
|
What is the Bohr effect? |
When co2 is present in haemoglobin, hydrogen ions displace oxygen on it - as result oxyhaemoglobin releases more oxygen to tissues Where tissues are respiring more = more Co2 as result - more hydrogen ions produced in RBC - makes oxyhaemoglobin release more oxygen More co2 present = haemoglobin less saturated w/oxygen Makes oxyhaemoglobin curve shift down and right |
|
|
What does the Bohr effect result in? |
Oxygen being more readily released where more carbon dioxide is produced -from respiration What muscles need for aerobic resp |
