Gene Expression Transcription and Translation DNA RNA (Ribonucleic Acid) Protein
Found: In the Nucleus Purpose: Carry information for making proteins Bases: A Adenine T Thymine C Cytosine G Guanine Strands: Two Length: Long Hundreds or thousands of genes DNA
Found: In the Nucleus and Cytoplasm Purpose: To carry information from DNA to RNA Bases: A Adenine U Uracil C Cytosine G Guanine Strands: One Length: Short One gene long RNA
Types of RNA tRNA mRNA rRNA
Types of RNA • Types of RNA • rRNA (r = ribosomal) • Purpose: Part of the ribosome, • Shape: Globular in shape • mRNA (m = messenger) • Purpose: To carry information from the nucleus • Shape: Long, thin strand • tRNA (t = transfer) • Brings amino acids to the ribosome • Shape: Cloverleaf
RNA polymerase mRNA
Steps to Transcription • RNA Polymerase attaches to the promoter • RNA polymerase attaches bases until the termination sequence is reached • Once termination sequence has been reached, the new RNA is released • Can be mRNA, rRNA, or tRNA
Now What? Transcipt is used to make protein! Where? The Ribosome!
The Genetic Code • Genetic Code • Term for the rules that relate how a sequence of nitrogenous bases in nucleotide correspond to an amino acids • Codon • Set of three nucleotides that encode an amino acid, start signal or stop signal • Start codon signals where translation starts • Stop codon signals where translation ends
Ribosome Purpose? Bases? Found?
mRNA Bases? Purpose? Found?
tRNA Bases? Purpose? Found?
Translation • mRNA attaches to the ribosome • tRNA carries complementary anticodon and amino acids to the ribosome • Peptide bond forms between the amino acids and tRNA is released • This process continues until the stop codon is reached • There is no anticodon for the stop codon • Protein is released