watch Antibiotic resistance is taught at a basic level at key stage 3 and in slightly more depth at GCSE. However, this tutorial is aimed at A Level.
click Antibiotics normally work by weakening the cell wall. The antibiotics prevent the formation of peptide crosslinks. Water then enters the cell and the cell wall cannot withstand the pressure of the water and so the cell bursts which causes osmotic lysis.
siti sicuri per opzioni binarie conto demo However, due to random mutations it is possible for a single bacterium to gain resistance to an antibiotic. There are several ways that this can occur, but you need to know that the bacteria can produce a protein which is an enzyme that can break down the antibiotic.
trading it Once a bacterium has gained resistance, it is possible for it to either pass a copy of the gene onto another bacteria. This process is known as conjugation (Horizontal gene Transfer) or it can be passed onto daughter cells produced by the bacterium this is known as vertical gene transmission.
How To Get Viagra Prescription in Hollywood Florida The Image below shows Horizontal gene transfer or conjugation. This image was supplied by Alila Medical Media. For more images of cells click on the link. This topic is normally taught at AS on AQA and A2 on OCR.
http://www.fishsiestakey.com/fiopre/579 In the first diagram the conjugation tube starts to form.
However, on opcje binarne wycena OCR the free DNA strand moves through the conjugation tube into the recipient cell and then replication starts to copy the DNA in both donor and recipient cells.
tricor 160 mg tablete The conjugation tube will then close and the cells will move apart