Which enzyme forms carbonic acid? → Carbonic anhydrase
Which ion moves into the RBC during the chloride shift? → Cl⁻
Name the effect where CO₂/H⁺ shift the O₂ curve right. → Bohr effect
Name the effect where deoxygenation boosts CO₂ carriage. → Haldane effect
Recall Feynman: explain to a 12-year-old
Imagine blood is a school bus. Oxygen kids get on at the "lungs" bus stop, sitting in special iron seats on a bus called haemoglobin. When the bus reaches a "hungry muscle" stop, the kids get off. The bus also has to take out the trash — the trash is CO₂. Most of the trash gets crushed into small compact packets (bicarbonate) so a lot fits on the bus. And here's the clever part: when the bus is full of trash and it's smelly (acidic), the oxygen kids get off faster — exactly where the muscle wants them. At the lungs, the fresh air makes the trash pop back into gas and the bus breathes it out.
Dekho, blood mein oxygen aur CO₂ dono ko carry karna hota hai, lekin dono gases plasma mein bahut kam ghulte (dissolve) hain. Isliye body clever tarike use karti hai. Oxygen ka lagbhag 98.5% haemoglobin ke iron (Fe²⁺) par baith kar chalta hai — isse hum oxyhaemoglobin kehte hain. Yaad rakho, ye "oxygenation" hai, "oxidation" nahi — iron rust nahi hota, bas O₂ dheere se pakadta aur chhodta hai. Loading-unloading ki curve S-shape (sigmoid) hoti hai kyunki binding cooperative hoti hai: ek O₂ baithe to agla aasani se baith jaata hai.
CO₂ teen tarike se chalta hai: thoda dissolved (~7%), thoda haemoglobin ke amino group par carbamino ke roop mein (~23%), aur sabse zyada bicarbonate (HCO₃⁻) ke roop mein (~70%). RBC ke andar carbonic anhydrase enzyme CO₂ ko paani ke saath milakar carbonic acid banata hai, jo H⁺ aur HCO₃⁻ mein toot jaata hai. HCO₃⁻ bahar plasma mein nikal jaata hai, aur balance banane ke liye Cl⁻ andar aata hai — isi ko chloride shift (Hamburger phenomenon) kehte hain.
Do important effects: Bohr effect — active muscle mein CO₂, H⁺, temperature badhne se curve right shift hoti hai, matlab Hb wahi O₂ zyada release karta hai jahan zaroorat hai. Haldane effect — deoxygenated blood zyada CO₂ carry kar leta hai. Dono ek team ki tarah kaam karte hain: tissue par O₂ nikalta hai to CO₂ chadhta hai, lungs par O₂ chadhta hai to CO₂ nikal kar exhale ho jaata hai.
Ye topic isliye important hai kyunki har breath aur har heartbeat isi chemistry par depend karta hai. Exam mein numbers (7-23-70), enzyme ka naam, chloride shift, Bohr vs Haldane — ye zaroor puchhe jaate hain, to inhe pakka kar lo.
