His is the short-form for the amino acid Histidine.
Histidine has imidazole as its functional group.
When it is in the protonated then the pKa of the side chain is 6 which lies in the physiological pH range of around ph6.
Due to this the catalysis of many enzymes have involves histidine for proton transfer. Histidine has the ability to abstract protons from amino acids such as cysteine, serine and threonine.
The abstraction of proton takes place with the help of the basic nitrogen present in histidine which abstracts the protons from the targets and then another molecule is used to act as a buffer and proton is abstracted from the acidic nitrogen.
Seismicity along divergent plate boundaries is concentrated along rocky areas away from the rift zones. An oceanic ridge marks divergent plate boundaries in the ocean basins. It is broad, fractured swell with a total length of 70,000 km. Basaltic volcanism and shallow earth quakes are concentrated along the rift zone at the ridge crest. The ridge's characteristics depend upon the spreading rate.
