Specific proteins transport many small molecules and ions. For instance, hemoglobin transports oxygen in erythrocytes. And proteins are also the major component of muscle. Antibodies are highly specific proteins that recognize and combine with such foreign substances as viruses, bacteria, and cells from other organisms. Hence, proteins mediated a wide range of other functions, such as generation and transmission of nerve impulses, control of growth and differentiation.
Proteins indeed play crucial roles in virtually all biological processes.
2.Msthews, C.K., and K.E. van Holde. They have also developed many innovative techniques to expedite the gene researches. It is expected that within the next few years the sequencing of three billion base pairs and the 50,000 to 100,000 genes in the 23 pairs of human chromosome would be completed. A gene is a segment of base pairs in DNA, of which the hereditary message determines the amino acid sequence of a particular protein molecule or polypeptide chain. DNA between each gene is called intergenetic area, or junk, because of its function is still unknown.