1. Protein Synthesis The process of protein synthesis is explained by the central dogma of molecular biology, which states that: DNA  RNA  Proteins How does the sequence of a strand of DNA correspond to the amino acid sequence of a protein?

2. Central Dogma of Biochemistry

3. What is DNA? DNA consists of a sequence of nucleotides Nucleotides are arranged in genes –one gene is a unique segment of DNA that codes for the manufacture of a particular protein DNA cannot leave the nucleus, but proteins are assembled in the cytoplasm To get from DNA, written in one chemical language, to protein, written in another, requires two major stages, transcription and translation.

4. Transcription and Translation During transcription, –This process is used to synthesize any type of RNA from a DNA template –A DNA strand provides a template for the synthesis of a complementary RNA strand –Transcription of a gene produces a messenger RNA (mRNA) molecule – which is used during protein synthesis During translation, –The information contained in the order of nucleotides in mRNA is used to determine the amino acid sequence of a polypeptide –Translation occurs at ribosomes

5. Transcription of DNA DNA contains the hereditary information for an organism DNA remains within the nucleus of the cell at all time In order for the original copy of DNA to stay pristine and protected, away from the caustic chemistry of cytoplasm a copy of the DNA called RNA is made which can leave the nucleus for protein synthesis

6. Transcription of DNA into RNA An enzyme begins to open the DNA between the nucleotide bases

7. Copying the DNA Strand The complementary RNA strand begins to grow

8. Transcription of DNA is Complete The mRNA molecule is complete and ready to leave the nucleus

9. What is RNA? RNA has the same primary structure as DNA. It consists of a sugar-phosphate backbone, with nucleotides attached to the 1' carbon of the sugar. The differences between DNA and RNA are that: RNA has a hydroxyl group on the 2' carbon of the sugar (thus, the difference between deoxyribonucleic acid and ribonucleic acid. Because of the extra hydroxyl group on the sugar, RNA is too bulky to form a a stable double helix. RNA exists as a single-stranded molecule. However,

10. Because of the extra hydroxyl group on the sugar, RNA is too bulky to form a a stable double helix. RNA exists as a single-stranded molecule.

11. Translation of RNA into Proteins Ribosome subunits attach to the mRNA to begin the process of building proteins

12. Translation continues

13. Translation of mRNA Complete

14. What is tRNA transfer RNA is a small RNA that has a very specific secondary and tertiary structure such that it can bind an amino acid at one end, and mRNA at the other end. It acts as an adaptor to carry the amino acid elements of a protein to the appropriate place as coded for by the mRNA.

15. Structure of tRNA