Molecules to Eye Color DNA, RNA and Protein Synthesis
(Chapter 8) DNA Deoxyribonucleic Acid Carries genetic information Found every cell Discovery of DNA Structure: nAFBs8&safe=active nAFBs8&safe=active
Structure Composed of chains of nucleotides Nucleotides have 3 parts Phosphate Deoxyribose sugar Nitrogen base 4 kinds- G,C,T,A
Chains have a “backbone” of phosphates and deoxyribose sugars Nitrogen bases sticking out
Nitrogen Bases
DNA is double stranded Another chain lines up with the nitrogen bases of the first G pairs with C and T pairs with A The bases (and strands)are held together by hydrogen bonds This forms a ladder shape ladder is twisted forming a double helix
DNA
“Unfolding DNA” Fold a piece of notebook paper into four columns
DNA Replication Makes 2 identical strands of DNA An enzyme called DNA polymerase “unzips” the two strands by breaking the H-bonds. Nucleotides with complimentary bases are attached to the exposed strands (If G is exposed, a C will be attached) This results in 2 identical strands
RNA Brain Pop! Ribonucleic acid Functions in turning DNA code into proteins 3 types Messenger, mRNA Transfer, tRNA Ribosomal, rRNA
Structure Chains of nucleotides 3 main differences between DNA and RNA 1. Ribose sugar (not deoxyribose) 2. Has U (uracil) instead of T (thymine) 3. Single strand (not double)
Protein Synthesis Converting DNA code into proteins Proteins are composed of chains of amino acids (AA)
Transcription mRNA is created from DNA 1. Section of DNA (gene) unzips 2. RNA nucleotides are paired with exposed bases
Unfolding DNA to mRNA
mRNA strand leaves the nucleus DNA zips back up
Codon- 3 base sequence of mRNA Anticodon- 3 base sequence on the tRNA
Translation mRNA codons are matched with tRNA anticodons. This places AA’s in a specific order.
AA’s bond together as tRNA release Creating a chain of AA’s with a specific sequence Chains of AA’s = protein