science - inside living cells

In a normal humans cell there are 23 pairs of chromosomes. A gene is a section of DNA which codes for inherited characteristics, such as having attached earlobes.

DNA molecules consists of two strands coiled to form a double helix. The stands are linked by a series of paired bases.Adenine,cytosine,guanine and thymine. A-T and C-T bases only link.

Protiens are molecules that the body requires to make hormones,skin and hair (growtth and repair)

organelles are speacialised structures found in the cytoplasm of the cells. Oraganelles called ribosomes are involved in protien synthesis.

Protien synthesis

1) DNA unravels at the correct gene

2) A copy of the coding strand is made to produce,RNA

3) Copy moves from nucleus to the cytoplasm.

4) The triplets code is decoded by the ribosomes

5) A amino acids join to other in the correct order to form a polypeptide.

Gentic engineering

sections of DNA that code for a specific protein can be transfered into microorganisms.the micro organisms then reproduce and make large quantities of the proteins. This can be used to produce lots of useful substances,e.g. bacteria can be used to produce large amounts of the hormone insulin for use by diabetics

1) The gene is identified…