AP Biology - Unit 6 - Protein Synthesis and Mutation

Deoxyribonucleic Acid, made of nucleotides

Nitrogenous bases, Sugar (Deoxyribose), Phosphate Group

Adenine, Thymine, Cytosine, Guanine

Transcription, mRNA Modifications, Translation

95% of DNA is junk DNA and does not code for a protein

RNA polymerase binds to DNA on promotor (TATA box) and makes complementary RNA molecule (messanger RNA)

inside the nucleus

• methylated cap goes on 5^1 end

• polyA tail goes on 3^1 end

• inteons are cut and removed, exons are glued together

• Alternative Splicing

same gene can make different proteins based on ghe way it is spliced

in the cytoplasm, mRNA becomes protein (amino acids)

ribosome binds to mRNA and finds a matching tRNA for each codon until reaching a Stop codon

group of three nucleotides

twenty amino acids

• 11 essential amino acids (comes from food)

• 9 made in body

2 types: substitution and frameshift mutation

One nucleotide change in DNA

3 outcomes: missense mutation, nonsense mutation, silent mutation

when a change in DNA causes a change in the amino acid sequence

when a change in DNA causes an early stop codon

when a change in the DNA does not change the amino acid sequence

when more than one nucleotide changes (chunk of DNA is either deleted or inserted, amino acid sequence always changes)

found in bacteria, required for the digention of lactose