RNA Structure and Function, Transcription and Translation

RNA (RIBONUCLEIC ACID) Function: All traits you have due to proteins of amino acids Genes contain “blueprints” to make protein Ribosomes are site of protein synthesis RNA reads blueprints & makes protein

Structure: Single Strand Sugar = ribose Phosphate group Bases = adenine, guanine, cytosine, URACIL (replaces T)

Types: mRNA: messenger (carries info to ribosome) tRNA: transfer (moves amino acids to ribosome) rRNA: ribosomal (makes up ribosomes)

Gene Expression: Transcription: RNA copy of gene made from DNA molecule Translation: Proteins made DNA RNA PROTEIN Transcription Translation

PRACTICE DNA = ATCGATACG Complementary DNA = mRNA = TAGCTATGC AUCGAUACG DNA = TCCGTACGA Complementary DNA = mRNA = AGGCATGCT UCCGUACGA

PROTEIN SYNTHESIS (TRANSLATION) The Genetic Code Every 3 nucleotides in mRNA code for specific amino acid; triplet or codon Genetic code is universal; same in all organisms tRNA anticodon is complementary to mRNA codon; picks up amino acids

THE GENETIC CODE mRNA CODONS

Exon – gene that is expressed; coding portion of dna Intron – gene that is not expressed; non- coding portion of dna

PRACTICE What amino acids are coded for by the following mRNA codons? GUC UAC AAA Val Tyr Lys CCG UCG GCA Pro Ser Ala What are the possible codons for the following series of amino acids? Phe – Tyr - Met UUU UAU AUG UUC UAC

What are the complementary mRNA codons to the tRNA anticodons? AAA ACG UCU UUU UGC AGA