By Dr Ananya Mandal, MD. Leptin is a protein hormone involved in the regulation of energy intake and expenditure by the body. Leptin is an important cytokine that plays a key role in the regulation of appetite, food intake and metabolism.y Dr Ananya Mandal, MD. Leptin is a protein hormone involved in the regulation of energy intake and expenditure by the body. Leptin is an important cytokine that plays a key role in the regulation of appetite, food intake and metabolism.
Report Abuse. PCR The polymerase chain reaction (PCR) is a technique widely used in molecular biology. It derives its name from one of its key components, a DNA polymerase used to amplify a piece of DNA by in vitro enzymatic replication.As PCR progresses, the DNA thus generated is itself used as template for replication. This sets in motion a chain reaction in which the DNA template is exponentially amplified.With PCR it is possible to amplify a single or few copies of a piece of DNA across several orders of magnitude, generating millions or more copies of the DNA piece.ith PCR it is possible to amplify a single or few copies of a piece of DNA across several orders of magnitude, generating millions or more copies of the DNA piece.
It is one of the most significant advances in science. The process involves copying a portion of DNA with a small molecular machine called polymerase, an enzyme, to duplicate DNA regions in a test tube. The process can be repeated to produce billions of DNA molecules in a few hours. Unlike other types of analysis, this DNA analysis process can reproduce DNA using a tiny sample of cells.