BIOL 208 Lecture Notes - Lecture 24: Carbonic Anhydrase, Cyanide Poisoning, Carboxyhemoglobin
19 May 2018
School
Department
Course
Professor
Anatomy 2
Lecture 24
May 1st 2018
Partial pressures
- Atmosphere made up of 3 gases:
- Nitrogen - 78%
- Oxygen - 21%
- Carbon dioxide - .04%
- Contribute to 760 mmHg sea level
Oxygen transport
- 98% of O2 transported via hemoglobin. Hb + 4(O2) = HBO2(4)
- Deoxyhemoglobin
- When hemoglobin is by itself
- Oxygenation
- When hemoglobin is paired with oxygen
- Deoxygenation
- When oxygen separates from oxygen and loaded onto tissues
2 inactive forms of hemoglobin
- Methemoglobin
- Result of cyanide poisoning
- From ferrous state to ferric state
- Iron can’t pick up oxygen
- Carboxyhemoglobin
- Connects with carbon monoxide - if carbon monoxide attaches to hemoglobin
- Hemoglobin has 200x greater affinity for carbon monoxide
Carbon dioxide transport ( Lecture supplement 10)
- Transported in 3 ways:
- 1) dissolves in plasma fluid - 7%
- 2) attached to hemoglobin ( carbaminohemoglobin) - 23%
- 3) bicarbonate ion (hco3-) - 70%
- Starts off as carbonic acid and separates into bicarbonate ion and hydrogen ion
- Co2 + H2O (in presence of carbonic anhydrase- CAD), reaction goes both ways
depending on concentration of reactant.
Document Summary
When oxygen separates from oxygen and loaded onto tissues. Connects with carbon monoxide - if carbon monoxide attaches to hemoglobin. Hemoglobin has 200x greater affinity for carbon monoxide. Transported in 3 ways: dissolves in plasma fluid - 7, attached to hemoglobin ( carbaminohemoglobin) - 23, bicarbonate ion (hco3-) - 70% Starts off as carbonic acid and separates into bicarbonate ion and hydrogen ion. Co2 + h2o (in presence of carbonic anhydrase- cad), reaction goes both ways depending on concentration of reactant. Start with co2 and finish with h2co3 (carbonic acid) Carbonic acid gives rise to hydrogen ion + hco3. When carbon dioxide is in an aqueous state (h2o) and carbonic anhydrase is present, causes formation of carbonic acid. Co2 + h2o (in presence of cad) = carbonic acid. Carbonic acid separates into hydrogen ions and bicarbonate ions. Hydrogen ions picked up by plasma proteins or by hemoglobin.
