Bishops Grade 12 Life Sciences Revision lessons DNA: The Code of Life
Content from CAPS • Deoxyribonucleic Acid (DNA) • Describe Location in the cell; nuclear DNA chromosomes, genes and extranuclear DNA; • - Describe Discovery of the structure DNA by Watson, Crick, Franklin and Wilkins; • -Learn Structure of DNA; • Describe the role of DNA: genes and non-coding DNA; • - Describe Replication: cell cycle (link to Grade 10): necessity for exact copy. • DNA Profiling • 1. State what a DNA profile is • 2. State the various uses of DNA profile • 3. State views for and against the use of DNA profiling. • Ribonucleic Acid (RNA) • Describe Types and location in cells; • Describe Structure of RNA; • Genetic code (basic understanding) • List similarities between DNA and RNA. • Tabulate differences between DNA and RNA. • Ribonucleic Acid (RNA) • Describe Transcription from DNA; • Describe Translation of RNA into proteins (protein synthesis) (mRNA, tRNA): sequence of events; and • - Genetic code (basic understanding).
Links to other sections – see Section A, Section B and Section C questions • Link to Genetics – gene and genotype, protein and phenotype, variation, mutations. • Link to Meiosis – chromosome structure, variation. • Link to Evolution – variation.
Read second letter here Read first letter here Read third letter here Second Letter First Letter Third Letter mRNA Codes for Amino Acids – know how this worksdata response
c mRNA molecule Structures Involved With Protein Synthesis Freeamino acids Nuclear membrane Free nucleotides DNA molecule Unloaded tRNA RNA polymerase Polypeptide chain Ribosome mRNA molecule Nuclear pores Cytoplasm Nucleus Label structures A-J
c mRNA molecule Processes Involved With Protein Synthesis tRNA recharged with amino acid Adding nucleotides to create mRNA Unloaded tRNA leaves translation complex Unwinding DNA molecule RNA polymerase tRNA with amino acid is drawn into the ribosome DNA molecule rewinds mRNA moves to cytoplasm tRNA adds amino acid to growing polypeptide Cytoplasm Nucleus
Possible questions – Section A • Definitions: DNA replication, DNA profile, gene, transcription, translation, protein synthesis, chromosome, genetic code etc
Possible questions – Section B – state similarities, tabulate or describe differences, draw, describe, state, explain, show, define, identify, label, calculate. Drawings to draw: • Draw and label a diagram to show a DNA nucleotide • Draw and label a diagram to show an RNA nucleotide Section B type of questions:
Possible questions • Sample of Section B questions
Possible questions – Section C (content 17, synthesis 3) • Describe the process of transcription and show how this differs from DNA replication. Explain the purpose of both transcription and DNA replication and state where and when each takes place in the body. • Describe the process of protein synthesis and the way in which this process would be affected by a gene mutation. • Describe the location, structure and functions of the DNA molecule and the process whereby copies of this molecule are made. • DNA replication ensures that exact copies of DNA are made in order for cell division to take place. However, in Prophase 1 and Metaphase 1 of Meiosis, events occur that ensure that there is variation in the chromosomes of daughter cells (gametes). Describe how DNA replication ensures exact copies of DNA are made and describe the events that take place in Prophase 1 and Metaphase 1 of Meiosis that bring about variation in gametes.