Post on 12-Aug-2018
DNA_Structure_2011.notebook
1
February 15, 2011
Mar 99:51 PM
Aim: What is the structure of DNA?
Do Now: Explain the Hershey Chase experiment and what was its conclusion?
Homework
Read pp. 298 299P.299 3,4,6.7
Go to website, verderbz.com Through the links, visit one of the websitesrelated to DNA. Write a 1 paragraph review of it.
Mar 1010:52 AM
Paperclip Combos
Material: 8 paperclips, 2 each of 4 different colors
Procedure:* Chose one letter to represent each color1 .Place any two paper clips side by side. Record the sequence from left to right.2 .Create new pairs of paper clips to produce as many different sequences as you can. Record the sequences.3.Next place 3 paper clips side by side to form a triplet. Record.4 Make as many triplets of different combinations as you can and record them.
Do Now
Mar 910:47 PM Mar 910:48 PM
Components of DNAStructure• a polymer• monomer units of DNA are nucleotides• polymer is known as a "polynucleotide." • each nucleotide consists of a 5carbon sugar (deoxyribose) + a nitrogen containing base attached to the sugar + a phosphate group• four different types of nucleotides found in DNA, differing only in the nitrogenous base • four nucleotides are given one letter abbreviations as shorthand for the four bases: A,C,G.T
Mar 910:48 PM
Components of DNA
Mar 910:56 PM
Adenine and guanine are purines. Purines are the larger of the two types of bases found in DNA
DNA_Structure_2011.notebook
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February 15, 2011
Mar 910:57 PM
Cytosine and thymine are pyrimidines.
Mar 910:59 PM
The deoxyribose sugar of the DNA backbone has 5 carbons and 3 oxygens. The carbon atoms are numbered 1', 2', 3', 4', and 5'
Mar 911:01 PM
FYI:A nucleoside is one of the four DNA bases covalently attached to the C1' position of a sugar. The sugar in deoxynucleosides is 2'-deoxyriboseThe four different nucleosides of DNA are deoxyadenosine (dA), deoxyguanosine (dG),
deoxycytosine (dC), and (deoxy)thymidine (dT, or T).
Mar 911:07 PM
DNA backbone is a polymer with an alternating sugarphosphate sequence. The deoxyribose sugars are joined at both the 3'hydroxyl and 5' phosphate groups to phosphate groups in ester links, also known as "phosphodiester" bonds.
Mar 911:10 PM
Features of the 5'd(CGAAT) structure:• Alternating backbone of deoxyribose and phosphodiester groups • Chain has a direction (known as polarity), 5' to 3' from top to bottom • Oxygens (red atoms) of phosphates are polar and negatively charged • A, G, C, and T bases can extend away from chain, and stack atop each other • Bases are hydrophobic
Mar 911:12 PM
DNA Double HelixDNA is a normally double stranded macromolecule. Two polynucleotide chains, held together by weak thermodynamic forces, form a DNA molecule.
DNA_Structure_2011.notebook
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February 15, 2011
Mar 108:47 PM
Aim: What is the structure of DNA? (Cont)
Do Now: What are the base pairs of DNA?
Homework: LE1 only:1. Take home Quiz to be CollectedP.463 464 #1 16 Answers only (1, 2,3 etc)
LE32. Read pp. 293 299
P. 299 #1, 2Describe the Hershey Chase Experiment
Feb 1510:01 AM
LE 3 2/15
Feb 158:43 AM
LE 1 2/15
Feb 157:21 AM
Mar 911:14 PM
Features of the DNA Double Helix• Two DNA strands form a helical spiral, winding around a helix axis in a righthanded spiral • The two polynucleotide chains run in opposite directions • The sugarphosphate backbones of the two DNA strands wind around the helix axis like the railing of a sprial staircase • The bases of the individual nucleotides are on the inside of the helix, stacked on top of each other like the steps of a spiral staircase. • Strands are complementary to each other, not identical
Mar 109:28 PM
DNA I Structure
a. Sugar Phosphate backboneb. Complementary pairs of nitrogenous basesA always pairs with TC always pairs with G• AT (AdenineThymine)• CG (Cytosine Guanine)
• Bases bonded together by hydrogen bonds
II Functiona. sequence of these bases encodes instructions b. some parts DNA are control centers for turning genes on and offc. some parts have no function, d. some parts have a function not yet understood e. other parts of DNA are genes that carry the instructions for making proteins these proteins build an organism and carry out life function ex: hemoglobin in red blood cells insulin
DNA_Structure_2011.notebook
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February 15, 2011
Mar 911:15 PM
Base Pairs• A forms 2 hydrogen bonds with T on the opposite strand,
• G forms 3 hyrdorgen bonds with C on the opposite strand.
Mar 1010:10 PM
How does a DNA Molecule copy itself?DNA REPLICATION
• Genes (the chemicals of heredity) are composed of DNA. Whenever new cells are made in either meiosis or mitosis, then new genes made of DNA are produced for the new cells.
• DNA Replication means the duplication of DNA that is identical to the original doublestranded DNA. Results in two, double stranded DNA molecules One old strand + one new strand
• This replication of DNA must be exact, or a mutation of an incorrect sequence of nucleotides will occur.
• DNA Replication occurs in 3 steps: **Many proteins are involved
1. DNA double helix unwinds (enzyme Helicase) and "unzips", forming two template strands as the bases (ACTG) come apart
2. Spare nucleotides (in the nucleus of the cell) attach themselves to the ‘broken rungs’ to repair the break (DNA polymerase) (Recall DNA is a Polymer) Each repairing nucleotide is identical to the one broken.
3. As each ‘broken rung’ is repaired, two ‘ladders’ form, that is 2 identical strands of DNA. The ‘repairing’ is really the process of replication.
Feb 157:26 AM Mar 128:56 AM
Aim: How does DNA send its genetic information out of the nucleus?
Do Now: What it called when DNA copies itself?
Homework 1. Complete the Transcription Lab2. Quiz Wednesday DNA, RNA, Protein Synthesis2. Read pp. 304 310, p.310 1,2,3,4
Mar 128:56 AM
Aim: How does DNA send its genetic information out of the nucleus?
Do Now: What it called when DNA copies itself?
Homework 1. Complete the Transcription Lab2. Quiz Wednesday DNA, RNA, Protein Synthesis
2. Read pp. 304 310, p.310 1,2,3,4
Mar 118:47 AM
Transcription: DNA to RNA• The nucleus controls all activity of the cell via the information contained in DNA• DNA never leaves the nucleus. • In order to get the information to the cell it uses Messenger RNA, which is complementary to DNA• Transcription: the process by which mRNA, a single stranded nucleic acid is formed using DNA as a template.• Usually copies only a portion of the DNA• Carries instructions for making a protein from a gene & delivers to the ribosome
Nitrogenous Bases pair similarly to DNAexcept that T is replaced by U (Uracil)
Complete the following:
DNA Strand: CGCGATCATGTGAACMRNA: GCGCUAG_________
DNAmRNA AU TA CG GC
DNA_Structure_2011.notebook
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February 15, 2011
Feb 152:16 PM
How does DNA direct Protein synthesis?
Mar 109:44 PM
Translation:Making Proteins mRNA to tRNA
Translation the process by which mRNA leaves the nucleus and provides the template for protein synthesis in the ribosome Translates the mRNA sequence into a specific sequence of amino acids tRNA have amino acids attached to them and bring them to the ribosome
Codon a triplet of three nitrogenous bases that codes for a specific amino acid, or to stop/ start the transcription
LE3 3/12/2010
Mar 161:50 PM Mar 129:29 AM
LE3 3/12/2010
Mar 109:44 PM
Translation:Making Proteins mRNA to tRNA
Translation the process by which mRNA leaves the nucleus and provides the template for protein synthesis in the ribosome Translates the mRNA sequence into a specific sequence of amino acids tRNA have amino acids attached to them and bring them to the ribosome
Codon a triplet of three nitrogenous bases that codes for a specific amino acid, or to stop/ start the transcription
Mar 169:05 AM
Protein Synthesis is diected by DNA and its use of mRNA & tRNA to carry the information from the nucleus to the cell cytoplasm & ribosomes
DNA_Structure_2011.notebook
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February 15, 2011
Mar 109:45 PM Mar 169:08 AM
Transcription & TranslationTCGATTGCA
mRNA
DNA
tRNAAmino Acid
Mar 109:45 PM
1. DNA2. nucleotide3. purines4. genes5. pyrimidines6. DNA helicase7. DNA polymerase8. DNA replication
a. represented by adenine and guanineb. enzyme that separates the DNA helix by breaking the hydrogen bonds
that link the nitrogenous basesc. instructions for inherited traitsd. the process by which DNA is copiede. represented by thymine and cytosinef. consists of a phosphate, a fivecarbon sugar, and a nitrogenous baseg. enzyme that adds nucleotides to exposed nitrogenous basesh. name given for deoxyribonucleic acid
DNA & RNA Vocabulary PracticeMatch the term/ word to its definition
Mar 1110:51 PM
a. codon b. gene expressionc. RNAd. transcriptione. translation
1 The process in which RNA is made from the information in DNA
2 Includes transcription and translation
3 A threenucleotide sequence that encodes an amino acid or a start/stop signal
4.A type of nucleic acid that includes three major types
5.A process that occurs at ribosomes where proteins are made from the information found in RNA
RNA Review