1. Nucleic Acids and Protein Synthesis

2. Central Dogma
DNA  RNA  Protein  Trait

3. DNA to PROTEINS
DNA is the blueprint for life – it contains your genetic information
The order of the bases in a segment of DNA (Gene) codes for a particular protein; these proteins then determine your traits
How do you get from a 4-letter code to an entire organism?
A GENE IS A SEGMENT OF DNA THAT CODES FOR A PROTEIN. NOT ALL DNA CODES FOR PROTEINS.

4. DNA to RNA: TRANSCRIPTION
In the first step of protein synthesis, the code of DNA is transcribed onto a molecule of RNA – this step of the process is known as Transcription
DNA is too big and too sensitive to leave the nucleus. However, proteins are made in the ribosomes, so the information in DNA must be transferred.
It will be transferred to a molecule of RNA
RNA is also used because it allows the genetic information to move from the nucleus (safe) to the cytoplasm (dangerous)

5. RNA RNA = Ribonucleic acid
It is still a nucleic acid – therefore it is made up of nucleotides (3 components: sugar, phosphate group and nitrogen bases)
It uses ribose as its sugar
Instead of using thymine, it uses uracil (A, U, G, C)
It is a single strand only

6. Types of RNA - mRNA
Messenger RNA (mRNA): single uncoiled chain that carries the genetic information from the nucleus to the cytosol

7. Types of RNA - tRNA
Transfer RNA (tRNA): single chain in the formation of a hairpin shape, each piece is bound to a specific amino acid

8. Types of RNA - rRNA
Ribosomal RNA (rRNA): most abundant form, wraps around ribosomal proteins to make up the ribosomes where proteins are made

9. Transcription
Process by which genetic information is copied (transcribed) from DNA to RNA
RNA polymerase initiates transcription by binding to a specific area of DNA called promoters
What do you think a promoter is?
A promoter starts, or promoters the beginning of transcription
Where the polymerase binds, the DNA strands separate and a template is created upon which RNA is created

11. Transcription (continued)
RNA polymerase attaches to the first nucleotide and adds on complementary bases using uracil instead of thymine
Continues until the polymerase reaches the termination signal
What do you think a termination signal does?
Termination signal causes the polymerase to release the DNA and RNA

13. Protein Synthesis
When mRNA is produced it will be used in protein synthesis or the production of proteins
Proteins consist of polypeptides which consist of amino acids
There are 20 possible amino acids

14. Translation: Protein Assembly
This process takes the information that was transcribed into mRNA and translates it into a protein
It begins when a piece of mRNA attaches to a ribosome
mRNA is “read” by the ribosome. It is read in segments of 3 letters called codons
Each codon codes for a specific amino acid. That amino acid is brought by a piece of tRNA which “transfers” amino acids.
tRNA is also read in segments of 3 letters called anticodons. The anticodon is complementary to the codon found on mRNA ( i.e. if the codon is AUG the anticodon is UAC)
Eventually a stop codon is reached. They do not code for amino acids. They tell the ribosome to stop adding amino acids.
Many ribosomes may work at once on one piece of mRNA

16. Genetic Code Correlation between nucleotides and amino acids
Codon: 3 mRNA nucleotides; codes for a specific amino acid
One codons codes to start (AUG – amino acid Methionine) and 3 codons can stop (UAA, UAG, UGA – no amino acids)
If you had a codon AAG, what amino acid would you have?
lysine