APG 201 Lecture Notes - Allosome, Main Source, Down Syndrome
Document Summary
2 types: messenger (mrna) and transfer (trna: differences between rna and dna, rna is: Contains the base uracil rather than thymine. Protein synthesis: transcription, nucleus, mrna, the two dna strands have partly separated. Free messenger rna (mrna) nucelotides have been drawn to the template strand and a strand of mrna is being made. Codon: each amino acid specified by sequence of 3 bases in mrna. Protein synthesis: assembly of an amino acid chain: amino acid chain= polypeptide chain= protein. Genes: sequence of dna bases responsible for the synthesis of a protein, a mutation occurs when the sequence of bases in a gene is altered. Mutation: main source of new genetic variation within a population, can be, beneficial, neutral, detrimental. Often results in a defective enzyme/ protein. Regulatory genes: control the expression of other genes, homeobox (hox) genes, evolutionarily ancient, directs the development of overall body plan and segmentation of tissues.
