Semi-conservative replication DNA Helicases DNA polymerases Transcription Codon Messenger RNA Transfer RNA. Molecular Genetics Unit

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1 Name: Unit 7 Molecular Genetics Students will be able to: Theme: DNA Heredity 6.1 Understand the structure and role of DNA Explain the structure of DNA (monomer and polymer) Discuss the process of DNA replication (basic steps, base pairing, semiconservative replication) 6. 2 Explain, based on evidence, how the structure of DNA determines the structure of proteins Identify the differences between DNA and RNA Understand that the different types of RNA (mrna, trna, rrna) carry out different roles in the process of protein synthesis Discuss the processes of transcription and translation Explain how different types of mutations occur (point, frameshift, stop, silent) and predict the consequences 6.3 Understand the recent advances in genetic research and the basics of biotechnology. Discuss the social significance of using different technologies. Understand the basics of various technologies: o Genetic engineering and how it affects DNA o Epigenetics and its influence on gene expression and DNA. o CRISPR and its role in editing the genome Keywords: DNA Double-helix Genes Nucleotides Nitrogen base Purines Pyrimidines Semi-conservative replication DNA Helicases DNA polymerases Transcription Codon Messenger RNA Transfer RNA Molecular Genetics Unit Date Topic 2/9 DNA Structure Notes 2/12 DNA Structure Model and Coloring 2/13 DNA Replication Notes 2/14 Protein Synthesis-Transcription 2/15 Protein Synthesis-Translation and Protein Synthesis Practice 2/16-2/19 NO SCHOOL-Teacher Inservice, Presidents Day 2/20 DNA Model Structure, Replication and Protein Synthesis 2/21 DNA Dan Activity 2/22 Mutation Notes and Card Activity 2/23 Ghost in Our Genes Video 2/26 Biotechnology Notes 2/27 Epigenetics Webquest 2/28 Molecular Genetics Unit FRQ and Review 3/1 Molecular Genetics Unit Test Anticodon Translation Mutations Trait Genetic Engineering CRISPR Epigenetics

2 2/9/18 Objective: Students will be able to describe the structure and function of DNA. 1. What are two things that I want you to know by the end of this unit? 2. When is your unit test? DNA Discovery 7.1 Structure of DNA Scientists originally believed proteins, not DNA, carried genetic information, due to the. o A series of experiments found that DNA was in fact the carrier of genetic information used x-ray diffraction to show DNA is a double helix used clues from the x-ray to build a model that explained the specific structure and properties of DNA What is DNA? Stands for: Carries our genetic material from one generation to the next in DNA is arranged in a -two strands are twisted around each other like a winding staircase. If you unwind a single human chromosome of DNA, it will be about What does our DNA do? Only about is made up of our genes. Up until recently, scientists believed that the rest of our DNA was noncoding-they thought these sequences were! However, a research project called Encode studied these sections and found: o Parts of the DNA that don t code for genes contain about : Determine when the gene turns on and off Switches for a variety of diseases Affects every cell, but can do so at different times in our lifetime Examples: Instructions for the cells to be different types of cells (brain cell vs liver cell) Instructions for pancreas cell to make insulin after a meal Instructions for cells to reproduce to replace dead or damaged cells (like skin cells replacing those that sloughed off). 2

3 Structure Nucleic Acids: o Nucleotides are made up of 3 things: A phosphate group (same on all nucleotides) 5 Carbon sugar molecule (same on all nucleotides) (Different on each nucleotide) Adenine (A) ( : 2 rings of Guanine (G) Carbon and Nitrogen) Thymine (T) ( : single ring of Cytosine (C) Carbon and Nitrogen) Draw a Purine and Pyrimidine in the space below: o o Base pairing: The phosphate of one nucleotide is attached to the sugar of the next nucleotide with a (strong) The base pairs on each strand of DNA are bound together with (weak) Purines are always paired with Pyrimidines o always pairs with (forms 2 hydrogen bonds) o always pairs with (forms 3 hydrogen bonds) This is called -the sequence on one strand determines the sequence on the other. DNA has a direction-it is polar! o It goes from the 5 end to the 3 end. o The opposite strand also goes from the 5 to the 3 end, 3

4 Structure of DNA: Use the following key to color the diagram of DNA: Phosphate group: Yellow Sugar: Orange Thymine: Red Adenine: Purple Cytosine: Blue Guanine: Green Hydrogen bonds: Pink 2/12/18 Objective: Students will be able to describe the structure and function of DNA. 1. Who is credited with discovering the structure of DNA? 2. Why did scientists think that proteins were the carries of genetic information, not DNA? 3. What does the diagram on the right represent? Label the 3 parts: phosphate, sugar, nitrogen base. 4

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6 2/13/18 Objective: Students will be able to describe the process of DNA replication: steps, enzymes, base pairs and semiconservative replication. 1. What nucleotide sequence represents the complement to the DNA strand: ATCGGATTC? 2. What Nitrogen bases are pyrimidines? Purines? 7.2 DNA Replication The complementary base pairing allows the DNA to be used as a during replication. DNA replication is simply making a of the DNA. We call this : the new strand contains one strand from the parent helix and one new strand. Steps of DNA Replication: 1. DNA Helicases (enzymes) between nucleotides allowing the 2 strands to separate. a. Other proteins attach to keep the strands from recoiling b. The areas where the DNA is separated is called a replication fork. 2. DNA polymerases (enzymes) move along each strand of DNA from the 5 end to the 3 end adding nucleotides to the exposed bases according to the base pairing rules (A-T/C-G). 3. DNA polymerase **The result is: Checking for errors: DNA polymerase has a role! o It can only add a new nucleotide if the one before it is correct. If it is not correct, the DNA polymerase has to back track and fix the wrong nucleotide before it can continue. The speed of replication: DNA isn t replicated by 1 DNA polymerase starting at one end and copying the entire strand. o DNA is replicated in (about 100 sections are being replicated at the same time). o This allows for a single strand of DNA to be copied in about. 2/14/18 Objective: Students will be able to explain the differences between DNA and RNA and the different types of RNA and their roles in protein synthesis and the steps of transcription. 6

7 1. Why is replication described as semiconservative? 2. What are the two enzymes that are used during replication? How do you know they are enzymes? 7.3 Protein Synthesis- Transcription A gene s instructions for making proteins are coded in the sequence of nucleotides. Making a protein happens in two steps: Both of these processes use the nucleic acid Ribonucleic Acid (RNA) A nucleic acid that is made up of linked nucleotides Differs from in 3 ways: o RNA is a of nucleotides, not two strands o RNA contains the 5 carbon sugar called, instead of deoxyribose o RNA has the nitrogen bases A, C, G and instead of A bonds with C bonds with U is considered a Transfer of DNA to RNA: Transcription Transcription (mrna Synthesis): Steps of Transcription: 1. RNA polymerase - 3 nucleotides in a specific sequence. Ex: AUG 2. RNA polymerase then two strands of the, exposing the DNA nucleotides on each strand. 3. RNA polymerase and then complementary nucleotides as it. o Transcription follows the same base-pairing rules as DNA, but U pairs with A instead of T. 4. RNA polymerase continues until it reaches a codon (UUA, UGA, UAG) 5. DNA closes by reforming after the RNA polymerase adds o the strand. Many strands of RNA are made at one time from a single double helix of DNA. 7

8 2/15/18 Objective: Students will be able to describe the process of translation and how the structure of DNA determines the structure of proteins. 1. What are the three ways the DNA is different from RNA? 2. In the RNA strand, what bonds with Adenine? In the DNA strand? 3. What is the purpose of transcription? Types of RNA: 7.4 Protein Synthesis- Translation : a form of RNA that carries the instructions from the DNA in the nucleus to the site of protein synthesis in the cell: o The instructions are written as 3 nucleotide sequences called codons o Each codon or start or stop signal for translation : a type of RNA that is found in the ribosome and accounts for 80% of the RNA found in the cell. : single strands of RNA that temporarily carries a specific amino acid on one end. o Contains the : a 3 nucleotide sequence on a trna that is to a codon on the mrna strand. Translation: o Takes place at the ribosomes, which attach to mrna and travel its length Steps of Translation: 1. mrna leaves the nucleus and joins to subunits in the. o The trna that carries the amino acid Methionine binds to the start codon on the strand,. o 2. The next codon on the strand binds to the on the strand carrying a specific 3. An enzyme binds the two amino acids carried by the trna, forming a 4. The trna detaches, 5. The ribosomes, containing rrna, moves down the mrna strand to the next codo. A trna carrying the amino acid. 6. to the amino acid chain and the trna detaches again. 8

9 7. Steps 2-6 are repeated until a stop codon is reached. o Stop codons are: UAG, UAA, or UGA o There is no complementary anticodon to these stop codons so there will be no trna to fit into this spot. When that happens, the amino acid chain is released into the cell. Summary of protein synthesis: In the nucleus, DNA uncoils and zips RNA nucleotides pair up with DNA bases to form mrna trna adds amino acids using the mrna strand All cells have the same DNA, but differ due to some genes being expressed in some cells and not others. Key: 9

10 2/16/18-2/19/18-NO SCHOOL-Teacher In-service and President s Day 2/20/18 Objective: Students will be able to describe how the structure of DNA determines the structure of proteins and how the genes lead to our traits. 1. Where is a codon found? An anticodon? 2. What is the start codon? 3. Where does transcription take place? Translation? 2/21/18 Objective: Students will be able to describe how the structure of DNA determines the structure of proteins and how the genes lead to our traits. Use the following mrna strand to answer the following questions. mrna strand: AUA/GGC/AGU/CCA 1. What is the original DNA strand that represents this mrna strand? 2. What are the anticodons for the mrna strand? 3. What portion of the protein molecule is coded for by the piece of mrna? (Hint: use your codon table) 2/22/18 Objective: Students will be able to explain how different types of mutations occur (point, frameshift, stop, silent) and predict the consequences to the protein. 1. If every cell contains the same DNA, why do different types of cells have different functions? 7.5 Mutations 10

11 What are mutations? Mutations: An organisms traits are based on their DNA sequence because: DNA sequence amino acid sequence protein shape function trait If there are changes in the DNA sequence, it can lead to changes in traits. Types of Mutations: : Change to one letter (base) in the DNA : Addition or deletion of a letter (base) in the DNA sequence. o Both of these shift the DNA so it changes how the codons are read. : Causes the protein to stop forming prematurely or causes continued translation beyond where the stop would be. : Changes in the number or structure of chromosomes : Mutations in the DNA that do not significantly alter the expression of genes. Causes of Mutations: External agents cause DNA to break down. o Examples: Environmental toxins, radiation, smoke, etc. 2/23/18 Objective: Students will be able to describe the recent advances in genetic research and the basics of biotechnology (CRISPR and Epigenetics) and discuss the social significance of using different technologies. 1. What is a mutation? 2. What are some causes of mutations? 3. Identify each type of mutation a. TCAGGCAGC becomes TCAGGAGC b. TCAGGCAGC becomes TCACGCAGC c. TCAGGCAGC becomes TCATGGCTAGC 2/26/18 Objective: Students will be able to describe the recent advances in genetic research and the basics of biotechnology (CRISPR and Epigenetics) and discuss the social significance of using different technologies. 1. None 7.6 Biotechnology 11

12 Biotechnology: the application of biological organisms, systems, or processes by various industries to learning about the science of life and the improvement of the value of materials and organisms such as pharmaceuticals, crops, and livestock. Genetic Engineering: o, including the transfer of genes within and across species o Uses, which is inserted into a host organisms, such as bacteria o Applications of Genetic Engineering: Genetically Engineered drugs and medicines 2/27/18 Using bacteria to produce proteins that the body does not make Antigens of harmful viruses can be inserted onto harmless viruses and injected into humans Genetically Engineered Crops: Drought resistant o Plants adapted to different environments o Resistance to weed killers, pesticides, or insects o Improving nutritional value (clustered regularly interspaced short palindromic repeats): a genetic engineering tool that uses DNA and associated proteins to. Epigenetics: the student of heritable changes in gene expression that Objective: Students will be able to describe their knowledge of molecular genetics on a unit review. 1. Go back to the front page of this packet and read through the essential outcomes. Put a question mark next to the topics that you still have questions about. Put a check mark next to the topics that you feel confident about. 2. How are you going to go about learning those topics that have a question mark next to them? 2/28/18-3/1/18 Objective: Students will be able to describe their knowledge of molecular genetics on a unit exam. 1. Turn in your homework to the basket. 12