"DNA Deoxyribonucleic Acid - PowerPoint"
DNA Deoxyribonucleic Acid “The Blueprint of Life” I. DNA Structure & Function A. What is DNA? 1. Organic molecule 2. Nucleic acid B.Where is it located? 1. Nucleus DNA 2. Chromosomes Chromosomes in Nucleus C. Structure of DNA 1. Nucleotides a. Phosphoric Acid b. Deoxyribose sugar c. Nitrogenous bases: Adenine-Thymine Guanine-Cytosine 2. Ladder Shape 3. Double strand, helix twist Ladder Shape (Sides & Rungs) Sugar Sides: Acid Phosphoric Acid T-A Sugar Sugar G-C Acid Phosphoric Acid C-G Sugar Rungs: A-T A-T T-A G-C C-G Watson & Crick’s Double helix: D. What is DNA’s Function? Hereditary Instructions Chemical code for every trait “Blueprint” for making Proteins Chromosome DNA Code: Genes = Hair Color Segments of DNA Code for Eye a trait Color DNA Chromosome Code: Acid Acid Sugar-T-A-Sugar Triplets= Acid Acid Sugar-G-C-Sugar Sets of 3 Acid Acid Sugar-C-G-Sugar Nucleotides Code for Trait DNA Chromosome Code: Like Morse Code: Hair *** *- ** *-* = Or DNA A-T A-T G-C C-G T-A C-G DNA Replication Chromosomes double Mitosis 2N Late Interphase 2N 2n to 4n E. Steps for DNA Replication: 1. DNA untwists 2. DNA unzips 3. Corresponding base pairs Line up In sets of 3 nucleotides (triplets) Or “codons” 4. DNA reforms 5. 2 strands twist into helix Identical Strand RNA Ribonucleic Acid “DNA messenger & taxi” II. RNA Structure & Function A. What is RNA? 1.Organic Molecule 2.Nucleic Acid 3. mRNA= messenger tRNA= transfer B. Where is RNA located? 1.mRNA in nucleus & mRNA cytoplasm 2.tRNA only mRNA in cytoplasm tRNA B. What is RNA’s structure? 1. Nucleotides= Acid a. Phosphoric Acid Sugar-Base b. Ribose sugar Acid c. Nitrogenous Sugar-Base Bases: Acid Adenine-Uracil Sugar-Base Guanine-Cytocine Acid 2. Single Strand Sugar-Base 3. No Twisted helix Comparison of RNA & DNA: Acid Acid Acid Sugar-Base Uracil Sugar-Base-Sugar Thymine Acid Acid Acid Sugar-Base Sugar-Base-Sugar Acid Acid Acid Sugar-Base Acid Sugar-Base-Sugar Deoxy- ribose Ribose Sugar-Base Acid Acid RNA DNA Ladder D. What are RNA’s functions: 1.mRNA= Copies the DNA code Deliveries message to Ribosome Protein Factories Why not send the original DNA code out? DNA might be Original DNA damaged! mRNA components mRNA copy are reused To copy more messages RNA function cont. Amino 2. tRNA: acid in cytoplasm Picks up an amino acid “Taxis” the tRNA aa to the Ribosome protein factories III. Protein Synthesis Assembling Proteins from the DNA Instructions A. Transcription: 1. mRNA is copied off of DNA 2. In nucleus 3. Steps: DNA untwists DNA unzips RNA codons line up Transcription: mRNA has: Ribose mRNA sugar A Uracil U instead of T thymine A C bases G Nuclear G membrane C allows it to DNA Code leave! Transcription in The nucleus DNA mRNA copy B. Translation = Conversion of the message (mRNA Code) Into a protein By the ribosome factories tRNA taxi B.Translation A 1. mRNA arrives at the Ribosome 2. tRNA picks up an U amino acid 3. tRNA delivers the aa to the C ribosome G 4. aa are assembled U A G C into polypeptide proteins mRNA code 4. Polypeptide Chain of amino acids grows 2. Peptide • tRNA bond forms delivers 3. tRNA leaves amino acid ribosome Summary: Protein Synthesis: DNA 1. Transcrition: Replication: Make mRNA Make From DNA duplicate DNA 2. Translation: In nucleus Make protein Copy the Off mRNA chromosomes code Using amino For Mitosis acids