Chemical Structure of Human Haemoglobin

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a) Describe the chemical structure of human haemoglobin (including diagram) b) Over the hundred variant of haemoglobin (caused by genetics mutation) have been describe to date, select one variant found in human (e.g Hb s) discuss the prognosis of named disorder

The major purpose of moving a fluid in the body is provide a mass transportation over a distance where diffusion is inadequate or too slow.(Knut Schmidt-Nielsen, 1997, 5th edition), in term of but the transportation of oxygen and carbon dioxide by diffusion in human is insufficient, this distribution is enabled by a movement of fluid called blood, In effect human body use one molecule found in the red blood cell called haemoglobin, on the other hand the haemoglobin can be define as a molecule found in the red blood cell which deliver or transport oxygen to the rest of body muscles and tissues. In this our essay we are going to describe the chemical structure which form the human haemoglobin, so what is really a haemoglobin? Scientist have conclude that name haemoglobin is a combination of two names Hem and Globins , they continue to define that hem is iron compounded and contain a rise structure while Globin is a red protein the technical abriviation of the haemoglobin is Hb or Hgb, while this protein molecule remain so essential for the human survival tissues it has been proven by scientists that it drawn the oxygen from the lung and transport to different part of body , this has been made possible circulatory system which use three majors organs in the name of Heart, Blood, and Blood Vessel. According to Cecie Starr and Ralph Taggart (1989) firstly they define the Blood is a fluid as ‘ a fluid connective tissue composed of water, diverse solute, and formed elements. Secondly the Heart as a muscular pump that generates the pressure needed to keep blood flowing throughout the body. Thirdly the Blood vessel as tubes of varying diameter through which blood is transported. (Cecie Starr,& Ralph Taggart 1989).

Beside the haemoglobin being a protein, it is made up with four polypeptides subunits, in the this can be illustrate in the picture below :

Figure 1 This is αβ tetramer of human haemoglobin. it illustrate the structure of the two identical α subunits (red) is similar to but not identical with of the two identical β subunits (yellow). The molecule contains four heme groups (black with iron atom shown in purple (Jeremy M.Berg, John L. Tymoczko, Lubert Stryer, 1995, pp 64 )

In this picture we have two different colour represent the subunits α and β bind together this is a structure representation of a haemoglobin; the two paired colour are red, yellow, and black with atom in purple each colour represent a polypeptide. The black colour represent a Hem bonding with the an atom in purple. by this we can see clearly that every subunit has it own hem group attached to it where the oxygen bind together. This picture on figure 1 was borrowed throughout scanning from the book of (Jeremy M.Berg, John L. Tymoczko, Lubert Stryer, 1995 Biochemistry fifth edition page 64 )` In most human the haemoglobin is a tetramer (meaning it contain four subunits as seen in the figure 1 ) and it is called haemoglobin A. In effect it is said that the hem and globin require to be produced at the same relative amount as excess of one lead the other one to be avoided. So far we have talk about hem, globins and polypeptides, is that all ? No! Scientist say that the red pigment found in the muscles is called the Myoglobin, and it main role is to provide the reservoir of oxygen in the muscle of the cell. it take up the oxygen from the blood and then give it up to be used by the mitochondria inside the cell for energy generation. It consist of a single hem molecule bound to a single protein molecule. (William H. Elliot & Daphne C. Elliot, 1997)

Early on we said human haemoglobin is called...
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