Myoglobin, Biology


We can build up the structure of haemoglobin by considering a single unit or monomeric form caned myoglobin. This consists of a single polypeptide chain the globin in which the haem group is embedded. Myoglobin is found in striated muscles of vertebrates and combines with one molecule of oxygen. The vertebrate haemoglobins are tetramers formed by the aggregation of four polypeptide chains each containing a discrete haem group. Thus each haemoglobin can combine with four molecules of oxygen forming oxyhaeomoglobin in a reversible reaction and the unoxygenated compound is called deoxyhaemoglobin.

Two monomers in human haemoglobin are of a type called s and the other two are P type. Nearly all vertebrate haemoglobins are tetramers but invertebrate haemoglobins are more diverse. The most distinctive feature is that the subunits often form large aggregates of relative high molecular weights. In mammalian blood the amount of physically dissolved oxygen is about 0.2 ml of oxygen per 100 ml of blood. The amount found bound to haemoglobin is 20 ml oxygen per 100 ml of blood. The dissolved oxygen is therefore, almost insignificant in animals without respiratory pigments. The only exception is the antarctic fish which lacks a respiratory pigment  altogether. The explanation could be that at low temperature, the metabolic rate is low and oxygen like other gases has higher solubility at low temperature.

Posted Date: 1/15/2013 7:54:26 AM | Location : United States

Related Discussions:- Myoglobin, Assignment Help, Ask Question on Myoglobin, Get Answer, Expert's Help, Myoglobin Discussions

Write discussion on Myoglobin
Your posts are moderated
Related Questions
Explain the Colorimetric Method Glucose Estimation? Alkaline copper reduction methods are by far the most commonly used methods for glucose estimation. This time honoured metho

Tlie phylum Cnidaria or Coelenterata, includes the faliiiliar hydras, jelly fishes, sea anemones and corals. You have olreacly studied about Cnidarialis in Units 4 and 7 of LSE-09

What is Defective Colour Vision Defective colour vision is often called colour blindness. The ability to appreciate one or more of the primary colours is lacking. This can be e

Biological diversity is the new buzzword, the magic door to international funding and global travelling. We share the earth with million of other living beings. Just as we humans m

Permanent Partial Disability - Injury from an Accident Permanent partial disability restrains the worker by doing the job he has been doing. He recovers from the injury in th

Why do preserved foods not spoil? Plant and animal cells must stay in an isotonic, or neutral, solution to survive. When salt or sugar is added, more of the cells wither and di

Importance of vitamin D Vitamin D is mainly involved in the  calcium and phosphate metabolism. It usually promotes absorption of calcium and inorganic phosphate from the intest

Explain Fontan Operation ? The original Fontan operation was done in a case where classical Glenn operation had been done (end-Lo-end anastomosis of superior vena cava and lig

DISSOCIATIVE  (CONVERSION) DISORDERS: There is normally a considerable degree of conscious control over the memories and sensations that can be selected for immediate attentio

Does the trend of the change in shape of the graph as temperature increases differ when a different gas is examined?