1. What do we know about DNA? Where is DNA located in the cell?Nucleus What does DNA stand for?Deoxyribonucleic acid DNA is a polymer. What is DNA made of? Nucleotides = monomers Nucleotide: Deoxyribose sugar Phosphate group Nitrogenous base (A, T, C or G) Function:Stores genetic information = CODE Hydrogen bonds

2. What do we know about RNA ? What does RNA stand for? What is the name of RNA sugar? RNA has instead of Thymine. How many strands does RNA have? Ribonucleic acid Uracil Ribose One mRNA, rRNA, tRNA

3. The three main types of RNA mRNA carries coded instructions for protein synthesis from nucleus to ribosomes rRNA – ribosome (site of protein synthesis) tRNA – carries specific amino acids to ribosomes during protein assembly

4. What do we know about proteins ? What are proteins made of? What are some examples of proteins? Amino acids? Enzymes, antibodies, hemoglobin, hormones, muscles.

5. What do we know about the genetic code (for a protein) There are four DNA bases: Adenine, Thymine, Cytosine, Guanine The DNA bases complimentary to each other: A-T & C-G Three nitrogenous bases code for one amino acid (triplet = codon, or a 3-base code) Gene is a section of DNA that codes for a specific protein (sequence of amino acids).

6. Each codon is made up of 3 letters and there are 4 possible letters: 4 x 4 x 4 = 4 3 = 64 possible combinations of codons - Only 20 amino acids are found in proteins How many codons are possible? Possibilities : - 44 codons (64 – 20) do not code for any amino acid (wasteful) More than 1 codon can code for the same amino acid

7. Universal Genetic Code

8. Learning Check What does the sequence of nitrogenous bases code for? Sequence of amino acids in protein (polypeptide). What is genetic code based on? Codons (triplet bases) What is a gene? A segment of DNA - a code for making a protein.

9. Code Breaker Decode the message hidden in the words Clue: CAPITAL Life Overcomes Nothing Greater Than Itself Minus Everything. Now Only Seems Extremely Easy. Jumping Under Something Terrible, Another Quirkily Useless Idiot Crafted Knives. Verify it Stayed In There To Hurt Openly Unique Goat Herders.

11. The Central Dogma TRANSCRIPTION Nucleus TRANSLATION Ribosome (cytoplasm)

14. A section of DNA (_____) is copied into mRNA DNA  mRNA Transcription gene 1. An enzyme unwinds and unzips DNA (breaks it’s ___________ bonds) on the section to be transcribed. hydrogen

15. DNA  mRNA Transcription AUG CCG UAA 2. An enzyme, RNA polymerase, READs the DNA by adding new RNA nucleotides (A; U; C; G) to the _______________ DNA bases on the DNA template strand. Ex. DNA triplet: TTC GGC ATT mRNA: complimentary

16. DNA  mRNA Transcription 3. Hydrogen bonds holding mRNA strand to DNA are broken. 4. DNA __________ into its ______________. retwistsdouble helix

17. DNA  mRNA Transcription 5. mRNA splicing – before it leaves the nucleus:  Introns - noncoding regions (“junk”)  Exons – coding regions (will be expressed)

18. DNA  mRNA Transcription 6. Transcription is complete. 7. Mature mRNA leaves the nucleus through a nuclear pore and travels to the __________ in the cytoplasm ribosome

19. Learning Check Where in the cell does transcription take place? Nucleus What is the purpose of transcription? Make a copy of the DNA message (instructions) for synthesizing a protein. What is the product of transcription? mRNA Why does DNA need a messenger? DNA never leaves the nucleus (too big to exit)

20. TRANSLATION mRNA  Protein Process of READING the ________________and translating them into the language of ______________ (protein). mRNA Codons AMINO ACIDS

21. TRANSLATION mRNA  Protein Process of READING the ________________and translating them into the language of ______________ (protein). mRNA Codons AMINO ACIDS

22. TRANSLATION mRNA  Protein 1. mRNA brings genetic sequence (instructions) to the ____________ (rRNA) in the cytoplasm to make a _____________. AMINO ACIDS ribosome protein

23. TRANSLATION mRNA  Protein 2. The rRNA (ribosome) decodes the copy of the DNA code carried by the mRNA in 3 letter chunks called a codon: |**AUG| CCG|UAA| Translation begins with a ***AUG (Methionine) - START codon

25. TRANSLATION 3. Each codon (3 bases) on mRNA corresponds to a specific Amino Acid (AA). There are 20 different AA.

26. TRANSLATION 4. Transfer RNA (tRNA) picks up a floating AA in the cytoplasm and brings it to the ribosome. 5. Here tRNA anticodon meets the mRNA codon to align according to the rules A-U; C-G. 6. Once aligned, tRNA drops its AA off and leaves the ribosome. Another tRNA brings the next AA. Protein (polypeptide) Amino acid Glycine

27. TRANSLATION 7. Peptide bonds form between amino acids Protein Sequence = Order of the amino acids

28. TRANSLATION

29. Translation termination 8. Process repeats. Translation continues until it hits a STOP codon (Ex. UAA) and the polypeptide (protein) is released. STOP codons: UAA, UAG or UGA

30. Learning Check Where in the cell does translation take place? Cytoplasm on the ribosome What is the purpose of translation? Translate the language of mRNA codons (bases) to the language of amino acids (protein). What is the product of translation? Protein (polypeptide)

31. An overview of protein secretion in eukaryotic cells: Ribosome Step 1: Protein (polypeptide ) is transported to the ER. Modification of a protein begins here. Step 3: Intra- Golgi vesicle transport Step 2: Transport vesicle take proteins to the Golgi apparatus Step 4: Proteins that will leave the cell are packaged in secretory vesicles. Proteins that remain in the cell are packaged in lysosomes (digestive enzymes) or storage vesicles. Most protein gets transferred from a RIBOSOME on the ROUGH ER to the Golgi apparatus.

33. Universal Genetic Code