2. DNA: genes on chromosomes

3. DNA is composed of nucleotides A Nucleotide has: - Deoxyribose Sugar - Phosphate - Nitrogen Base Adenine Thymine Guanine Cytosine A - T and G - C

4. DNA is a helix molecule Hydrogen bonds are in between the bases. Note the nucleotides pairing.

5. DNA self replicates before cell division

6. The DNA strand opens and will add nucleotides. A to T and G to C. 5’ 3’ 5’3’ C A G T One strand grows continuously, the other grows discontinuously. Enzymes join the strands.

8. DNA produces proteins in two steps Transcription: mRNA production Translation: protein production

9. Transcription is when the mRNA produced. mRNA from DNA as expected…….. GGG CCC TTT AAA CCC GGG AAA UUU The bases of the DNA are matched up with the RNA bases A-U, T-A, G-C, C-G AAA TTT GGG CCC GGG CCC TAA UUU AAACCC GGG CCC GGG AUU

10. Synthesis starts at the beginning of a gene

11. Transcription moves in a 5’ to 3’ direction

13. Transcription finishes as mRNA is released

14. The DNA triplets help code for amino acids during translation because DNA is in control of the triplets of mRNA (the codon). The anti- codon of the tRNA matches this codon on the ribosome and brings with it an amino acid. UUU AAACCC GGG CCC GGG AUU AAA | Phe UUU | Lys GGG | Pro CCC | Gly GGG | Pro CCC | Gly UAA | Ile Bonds form between amino acids

15. When the chain is complete, a new protein has been formed. Video of Protein Synthesis.

17. On the ribosome mRNA codons match tRNA anticodons linking amino acids

18. Steps to Protein Synthesis Transcription: Production of mRNA by DNA in nucleus. Base pairs match up A to U and G to C (RNA has no Thymine). Translation: In the cytoplasm, on the ribosome, the mRNA codon matches tRNA anticodon to bring the proper amino acid in for bonding. Once the whole mRNA is read by the ribosome, the stop codon ends the production of the peptide chain; the protein is complete!

19. How is RNA different than DNA? Ribose Sugar Uracil for Thymine Single strand not self replicating found all over the cell

20. Nucleolus - Site of ribosome production Nucleus - location of DNA, cell organizer Chromosomes - coiled chromatin Chromatin - DNA and proteins not coiled DNA - helix shaped molecule with base sequences that make up the genetic code RNA - made by DNA, assists DNA to make proteins as a messenger (mRNA), transfer molecule (tRNA) and ribosomal RNA (rRNA).

21. END!