Hemoglobin Model

Hemoglobin model: note the 02 being carried by molecule. Pipe cleaners=subunits Green marsh mellow=iron molecule Yellow marsh mellow=oxygen molecule Orange cards= heme groups (wolfe, 2000)Oxygenated/deoxygenated oxygenated †¢ 02 bound †¢ Bright red †¢ Subunit is in relaxed form †¢ Higher affinity for 02 †¢ Affinity for oxygen is  cooperative, which means  that the affinity for 02  increases with each bound  molecule. ( Ahern & Rajagopal, 2013)Deoxygenated †¢ 02 not bound †¢ Dark red color †¢ In tense form which has lower affinity for oxygen. †¢ When 02 binds to  deoxygenated hemoglobin,  hemoglobin transitions from T  state to R state. This occurs  when 02 binds to iron, it  causes a change in the  subunit. ( Ahern & Rajagopal,  2013)Bohr Effect Hemoglobin has a high affinity for 02 at a high PH, low Co2. Hemoglobin has a lower affinity at a low PH, high Co2.  At a high Co2, low PH hemoglobin is more stable in the T state which decreases its affinity for 02. Oxygen needs to be delivered to the tissues. Tissues have a low PH. Hemoglobin needs to release 02 at low PH. Low PH = low 02 saturation.  ( Wolfe,2000 )Myoglobin: wants to store 02 for when tissues need it. Has a higher affinity than hemoglobin. ( Ahern & Rajagopal, 2013) Hemoglobin: wants to unload 02 in the tissues. Has a lower affinity than myoglobin. ( Ahern & Rajagopal, 2013 )  (Genetic science learning center, 2013)Difference between normal and sickle forms of hemoglobin.Normal and sickle RBC’s at the cellular level.  (Genetic science learning center, 2013)Diseased RBC’s vs. Normal RBC’s Diseased †¢ Have a sickle shape, and are  thick and sticky. Clumps  together in small blood  vessels. †¢ Blocks normal hemoglobin  to deliver 02 to tissues. †¢ Short life span of 10-20 days †¢ Body can not keep up with rbc production leading to  anemia and pain. (Wolfe,  2000)Normal †¢ Round †¢ Doughnut shape †¢ Life span of 120 days (Wolfe, 2000)  (Ahern and Rajagopal, 2013)