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E. coli normally metabolise glucose, but if glucose is not available in a new environment, the lac operon can allow E. coli to metabolise lactose, the sugar found in milk using the structural genes beta-g...

Osmosis is the passive movement of water through a partially permeable membrane from a high concentration of water to a low concentration of water. An example of this is when water moves from soil into a ...

DNA and mRNA are both nucleic acids and are made up of a sugar, phosphates and a base. However, they are very different. Firstly by simply looking at the molecules DNA is double stranded whereas mRNA is s...

Polymerase chain reaction (PCR) is a technique used in molecular biology to amplify a single copy or a few copies of a segment of DNA across several orders of magnitude, ...

The external intercostal muscles contract which moves the diapraghm upwards. This reduces the volume of the thorax and therefore with less space, the pressure in the lungs goes up. The pressure in the lun...