Question

I don’t understand hemoglobin plz explain

Know that hemoglobin is a homodimer of a and b heterodimers and that the a and b monomers are structurally similar to one another and to myoglobin, but not identical

Know how O2 binds to hemoglobin and the roles of the porphyrin, iron (together called heme group), distal His, and proximal His Know why O2 is poorly soluble in the blood and why hemoglobin is thus essential for life

Know how the 4° structure of hemoglobin allows it to sense and respond to [O2 ]

Know the structural difference between the T (tensed) and R (relaxed) forms of hemoglobin and what this means for the structure of the porphyrin ring and the affinity of hemoglobin for O2

Answer 1

the myoglobin has the more affinity for oxygen than the haemoglobin, but haemoglobin releases oxygen more easily than that of myoglobin, this will leads that the haemoglobin can carry oxygen to all parts of the body and even myoglobin also used as well, particularly for carrying oxygen to muscle cells.

with the help of four heme groups and one globin group, the haemoglobin forms a tetrahedral structure(globin surrounded by heme groups). the heme group is usually composed of a ringlike organic compound known as a porphyrin to which an iron atom is attached. and the iron atom that binds oxygen as the blood travels between the lungs and the tissues.

the affinity for oxygen of T(tense) state is usually lesser than that of R(relax) state, it is because that the T(tense) haemoglobin lacks in oxygen species. so, it is a deoxy form of haemoglobin and called as deoxyhemoglobin.

R-is fully oxygenated and also known as oxyhemoglobin.

The higher the affinity of a given protein for oxygen, the harder it will be for that protein to release oxygen when the time comes. Thus, haemoglobin's lower affinity for oxygen serves it well because it allows haemoglobin to release oxygen more easily in the body.