RNA and Protein Synthesis 12-3. Genes Genes are coded DNA instruction that control the production of...

RNA and Protein RNA and Protein SynthesisSynthesis

12-3

GenesGenes

GenesGenes are coded DNA instruction are coded DNA instruction that control the production of that control the production of proteins within the cellproteins within the cell

the first step in decoding the the first step in decoding the message of DNA is copy part of the message of DNA is copy part of the nucleotide sequence from DNA to nucleotide sequence from DNA to RNARNA

Structure of RNAStructure of RNA

Almost the same as DNA – they are Almost the same as DNA – they are long chains of nucleotides – sugar, long chains of nucleotides – sugar, phosphate and nitrogen basephosphate and nitrogen base

3 main differences3 main differences– Different sugar Different sugar

DNA = deoxyrobose, RNA = riboseDNA = deoxyrobose, RNA = ribose

– DNA is a double helix, RNA is a single DNA is a double helix, RNA is a single strandstrand

– RNA has Uracil (U) instead of Thymine (T)RNA has Uracil (U) instead of Thymine (T)

Types of RNATypes of RNA

mRNAmRNA – (messenger) RNA molecule – (messenger) RNA molecule that carries copies of instructions from that carries copies of instructions from a gene to the ribosomea gene to the ribosome

tRNAtRNA – (transfer) type of RNA molecule – (transfer) type of RNA molecule that transfers each amino acid to the that transfers each amino acid to the ribosome ribosome

rRNArRNA – (ribosomal) type of RNA that – (ribosomal) type of RNA that helps make up ribosomes helps make up ribosomes

DNA vs RNADNA vs RNA

Protein SynthesisProtein Synthesis

Two main stepsTwo main steps

Transcription Transcription – Takes place in the nucleusTakes place in the nucleus

TranslationTranslation– Takes place at the ribosomesTakes place at the ribosomes

TranscriptionTranscription

TranscriptionTranscription is the copying of the is the copying of the information from DNA to mRNAinformation from DNA to mRNA

RNA polymeraseRNA polymerase is an enzyme that binds is an enzyme that binds to DNA and separates the DNA strands. to DNA and separates the DNA strands. Then it uses one strand of DNA as a Then it uses one strand of DNA as a template to make nucleotides of RNAtemplate to make nucleotides of RNA

The enzyme will only bind to a part of The enzyme will only bind to a part of the DNA know as a the DNA know as a promoterpromoter

TranscriptionTranscription

The Genetic CodeThe Genetic Code

Proteins get made by joining Proteins get made by joining together amino acids into long chains together amino acids into long chains called polypeptidescalled polypeptides

The language that RNA uses to The language that RNA uses to determine the amino acid sequence determine the amino acid sequence is called the genetic codeis called the genetic code

Every 3 nitrogen bases is called a Every 3 nitrogen bases is called a codoncodon or a “word” or a “word”

Each codon is a code for a different Each codon is a code for a different amino acidamino acid

TranslationTranslation

TranslationTranslation is when the cell uses the is when the cell uses the information on the RNA to produce information on the RNA to produce proteinsproteins

mRNA leaves the nucleus and mRNA leaves the nucleus and attaches to a ribosomeattaches to a ribosome

tRNA will bring amino acids to the tRNA will bring amino acids to the ribosomeribosome

AnticodonAnticodons on the tRNA will attach to s on the tRNA will attach to the codon of mRNA linking the amino the codon of mRNA linking the amino acids together in the correct orderacids together in the correct order

protein synthesis video