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A term referring to the theory that when a group of people collectively own a resource, individuals acting in their personal self-interest will inevitably overtax and destroy the resource. The theory was introduced by Garrett Hardin (1968) to modern discussions of population growth. Many global environment problems like ozone layer depletion are the consequences of [...]

Often one or more changes may occur abruptly in some attributes of a group of animals, with the aid of which the group may get adapted to a changed environment. Such change may not be beneficial under the existing conditions. Such adaptation is known as Pre-adaptation or Prospective adaptation (Simpson, 1958). On the other hand, [...]

Adaptation is the modification or change in the structural, functional and behavioural attributes of an organism for better survival and to cope with existing environmental conditions. Adaptations allow the animal to suit to the environment for better survival in the struggle for existence. It allows the animal to proceed through the evolutionary pathway.

The synthesis of the strand being extended in the overall 5′-3′ direction, called the leading strand and is continuous. The strand being extended in the overall 3′-5′ direction, called the lagging strand, grows by the synthesis of short fragments (= okazaki fragments). Thus the synthesis of lagging strand occurs discontinously

The type II topoisomerase in E. coli is also known as DNA gyrase. It is a treatment with two alpha subunits encoded by the gyrA gene and two beta subunits specified by the gyr B gene. These two genes were formerly known as nal A and cou gene.

The complete replication apparatus moving along the DNA molecule at a replication fork is called the replisome. The replisome contains the DNA pol III and primosome. The replication apparatus carries out semi conservative replication of DNA.

New DNA chain is initiated by a short RNA primer synthesized by DNA primase. The E. coli DNA primase is the product of the dna G gene.

Once the DNA strands are unwound by DNA helicase, they must be kept in single stranded condition. This condition is maintained by single-strand DNA binding proteins (SSB Proteins). in E. coli, the SSB protein is encoded by the ssb gene.

The unwinding process of two strands of DNA is catalyzed by enzymes called DNA helicases. The major DNA helicase in E. coli to the product of the dnaB gene. The helicases unwind DNA molecules using energy derived from ATA.

This is the point of origin of replication in the E. coli chromosome. This area has been characterised in detail. OriC is 245 nucleotide pairs long.