respiratory pigment.pptx

Types of respiratory pigment like hemoglobin, Myoglobin

1. Introduction Blood itself not carrier of the respiratory gases but contains a respiratory pigment which actually act as the carrier of the respiratory gases because this pigment has a special affinity for respiratory gases. The respiratory pigment in its nature varies in different animals. Respiratory pigment differ in their chemical constitution in different group of animals and even in the same phyla there may be several types of pigment. These pigment includes the cytochrome the flavoprotein and other colored molecules of protein called “ chromoprotein ” which are significance in the transport of respiratory gases and impart or definite color to the body fluid.

2. Defination A respiratory pigment is a molecule such as haemoglobin in invertebrates and other vertebrates , that increases the oxygen carrying capacity of the blood. or “ Respiratory pigment are coloured substance present in blood transporting the oxygen and carbon dioxide.” or “Respiratory pigment are circulatory pigment which mediate transfer of respiratory gases at the extracellular and intracellular level.”

3. Characteristics of respiratory pigment They are colored pigment . They have special affinities for respiratory gases . They are distributed either in the blood or in the body fluid. They are colored proteins which contain a metallic ion. The combines with oxygen and carbon dioxide and play key role in the transportation.

4. Type of respiratory pigment – 1.Haemoglobin 2.Haemocyanin 3.Chlorocruorin 4.Haemerythrin 5.Pinnaglobin 6.Echinochrome 7.Molpadin 8.Vanadiun 9. Neuroglobins 10. Cytoglobins

5. General account of respiratory pigment HAEMOGLOBIN :- Haemoglobin occurs in the blood plasma of invertebrates . It is also called erythrocrurin . It is a chromoprotein (conjugated protein). It is found in few holothurians , several crustaceans , chironomous insect , planorbis , annelids , parasitic nematodes , flatworm etc. Molecular weight - 68000 kDa . It is red in color metallic group present is IRON.

6. CHEMICAL STRUCTURE :- Haemoglobin is composed of two component namely a protein component called Globin & a non- protein component called Haem . Globin formed of four polypeptide chains of the four two are identical and called α ( alfa )chain each α chain formed of 141 amino acids . The other two identical chains are called β chain which contain 146 amino acids . The heam is formed of iron and porphyrin . The iron is present in the ferrous from. The porphyrin is the pigment and it gives red colour to the haemoglobin . There are four haem molecules in one haemoglobin .

7. When haemoglobin is treated with HCl , it is froms a brown colored pigment called “ acid haematin ” When haemoglobin is treated with Glacial acitic acid it froms “ haemin crystal ” .