The Polymerase chain reaction or PCR is a simple and easy method for the production of multiple number of copies of piece of DNA in vitro. This method synthesised large quantities of DNA fragment without the gene cloning. This technique was developed by Kary Mullis in California in 1985. He also share Noble prize for chemistry in 1993. The mechanism and detail of Polymerase chain reaction has been described by Erlich. The Polymerase chain reaction can be understood with the three steps: Denaturation or Melting of target DNA: The target DNA is heated at about 94 degrees Celsius for 15 second ..read more

Linn and Arber discovered that Escherichia coli is able to protect itself from the infection of bacteriophage  by a defence mechanism called restriction modifications system. This system has two component Restrictions enzymes and Methylase. Restriction enzymes belong to class nuclease which recognise specfic sequence of DNA. It is also called restriction enzyme because it stop the propagation of bacteriophage in Escherichia coli.  Methylase add methyl group to sequence of  bacterial DNA to prevent the harmful effect of restriction enzyme. Restriction enzyme is also restrictio ..read more

Biogas is one of the solution of energy in rural area. The gas which is produced from Bacteria by the anaerobic  action on organic matter called Biogas. Biogas comprises a mixture of methane as major constituent and along with carbon dioxide,  hydrogen sulphide and hydrogen. Special bacteria of group Archaebacteria  named methanogen are commonly used in production of Biogas. These bacteria break down  anaerobically cellulosic material available in dung of cattle and release biogas. Gobar gas or Biogas plant are frequently set up in rural area because large amount of dung ..read more

The domestication mestication and rearing of pig  or Sus scrofa domesticus for commercial purposes is called piggery. Pig has been widely used as diet by various tribes. Piggery stands at good position among the small scale industry because pig is cheapest and best among the farm animals. The oestrus cycle of pig is completed with in 20 to 21 days in normal condition. In mature pig the vulva start to swell due to release of orstrin hormone by the follicles. During this period if female pig mates two time than youg ones are produced more than normal mating. The mating period takes 3 ..read more

  Goat , Sheep Cow Buffalo, lamb,  snake, tigers crocodile etc are used  in leathers industry. Remember??The skin of cow is called as kips whereas the skin of Buffalo is called buffs. Process of skin industry Flaying -The traditional job of flaying is done by the hereditary peoples. During the process of flaying, some amount of flesh and tissue is attached with the skin to increase the weight of leather. This is also useful when a knife is used to cut the skin.The carcass is hanged with a pole with the hind limb upwards and peoples pulls the skin over the back of dea ..read more

Microbial production  is only source of vitamin B12 but vitamin B2 or riboflavin  is also manufactured up to some extent microbiologically. Remember ??only water soluble vitamin can be produced commercially with the use of microbes.  Any fat soluble vitamin has not been synthesised so far with the use of microbes.  Beta carotene which is converted into vitamin A , can be synthesised by use of  microbes. In nature, vitamin B12 is synthesised by metabolic activity of microbes. It is synthesised by bacteria streptomyces and not by any yeast or fungi. It also is said ..read more

  The pearls are of variable shapes and sizes. They may be white, or cream red or pink red in colour. The spherical pearls of rainbow colour are rarely found. The best quality of pearl is obtained from marine oysters. Pearl obtained from freshwater bivalves are not as valuable as those obtained. Pearl comprises of  Water: 2-4%, Organic matter:3.5-5.9%,  Calcium carbonate: 90% residue 0.1 to 0.8%                                                    &nb ..read more

  Lac is used in toys, bracelets, sealing wax also used in  filling ornaments, for manufacturing of varnishes and paints, for silvering the back of mirrors etc. Waste materials produced during the process of stick lac are used for dying purposes. Nail polish is a good example of the by-product of lac. Lac culture refers to the domestication and rearing of lac insects on the  scientific basis  to get  a high amount of quality lac. Lac is a kind of resin secreted by the lac in­sects. India is a major lac producing country followed by Thailand. Lac is best said to be a ..read more

  It has been regarded that the phylogeny of humans started from Gorillas and chimpanzees like Ape  who existed around fifteen million years ago. These were called Dryopithecus and Ramapithecus. It is to be believed that Dryopithecus were more app-like whereas Ramapithecus was more man-like. It is also to be believed that most of the evolution of humans takes place in East Africa like Ethiopia, Tanzania, Kenya. Although the remains of humans have been found in other parts of Africa, Asia and Europe. Fossil bones  with hominid features have indicated that man-like primates walk ..read more

  Population genetics is the study of gene frequency in the population and  their change under varied conditions. Population or Mendelian  population is a group of individuals present in a geographical area which has a common gene pool.  Gene frequency of the percentage of an allele in relation to the total allele  present in a population. All the genes and their alleles in the population create a gene  pool. A change in relative frequency of allele  brings the evolution. This occurs due to some selective pressure but normally the allele tries to maintai ..read more