Outline the process of protein synthesis in a cell.
1) Firstly, the instructions to produce a protein are contained within part of the DNA molecule called a gene.
2) This information is copied from the DNA to form another information-carrying molecule called messenger RNA (mRNA). This process occurs through enzymes called RNA polymerases.
3) The mRNA (unlike the DNA) can leave the nucleus of the cell (where almost all of the DNA is found) through pores in the nucleus.
4) It travels to the structures which assemble the proteins called ribosomes.
5) The ribosome reads the instructions contained in the mRNA and sets about joining together amino acids in the correct sequence instructed by the mRNA to form a protein.
6) The proteins then enter vesicles (sacs surrounded by membrane) which travel to the Golgi Apparatus.
7) The Golgi apparatus modifies the protein and then packages it again in a vesicle ready for release from the cell.
8) The vesicle travels to the cell membrane, fuses with it and then is released from the cell itself outside.
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