Tues 1/21. Today: Virus movie clip, ek paragraph for ch 20. Next class: collect Ch. 20 Guided Reading

Transcription

1 Tues 1/21 Today: Virus movie clip, ek paragraph for ch 20. Next class: collect Ch. 20 Guided Reading

2 Pg. 104 Ch. 20 Guided Reading Pg. 105 EK Paragraph 3C3

3 Wed. 1/22 Collect-Ch 20 Guided Reading Today: Notes-ch 20, Articles and diagrams. Homework: Finish diagrams.

4 Fri. 1/24 Collect: Nothing Today: Finish Ch 20 notes and E. coli Insulin Factory Next Class: Quiz-Ch 20, Transformation Lab? Homework: Experimental Organizer read lab very carefully!!!

5 In: pg 106 Tape in the Virus Replication Movie Clip Questions.

6 Pg. 107 Viruses and Bacteria Chapter 20

7 What you must know: The components of a virus. The differences between lytic and lysogenic cycles.

8 Bacteria vs. Viruses Bacteria Prokaryotic cell Most are free-living (some parasitic) Relatively large size Antibiotics used to kill bacteria Virus Not a living cell (genes packaged in protein shell) Intracellular parasite 1/1000 size of bacteria Vaccines used to prevent viral infection Antiviral treatment

9 Viruses Very small (<ribosomes) Components = nucleic acid + capsid Nucleic acid: DNA or RNA (double or single-stranded) Capsid: protein shell Some viruses also have viral envelopes that surround capsid Limited host range (eg. human cold virus infects upper respiratory tract) Replicate within host cells Replicate very quickly=rapid evolution.

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13 Simplified viral replicative cycle

14 Bacteriophage Virus that infects bacterial cells

15 VIDEO: T4 PHAGE INFECTION

16 Lytic Cycle of T4 Phage

17 Bacteriophage Reproduction Lytic Cycle: Use host machinery to make copies of virus Death of host cell by rupturing it (lysis) Virulent phages replicate by this method Lysogenic Cycle: Phage DNA incorporated into host DNA and replicated along with it Phage DNA = prophage Temperate Phage: uses both methods of replication

18 Lytic Cycle vs. Lysogenic Cycle

19 Animal viruses have a membranous envelope Host membrane forms around exiting virus Difficult for host immune system to detect virus

20 Retrovirus RNA virus that uses reverse transcriptase (RNA DNA) Newly made viral DNA inserted into chromosome of host Host transcribes viral DNA (= provirus) to make new virus parts Example: HIV (Human Immunodeficiency Virus) RNA viruses lack replication repair mechanisms and mutate very quickly.

21 HIV = Retrovirus

22 HIV Infects white blood cells HIV+: provirus (DNA inserted) AIDS: active viral reproduction

23 VIDEO: HIV LIFE CYCLE

24 Other human viruses Herpes virus Smallpox Herpes Simplex Virus 1 (HSV-1) Herpes Simplex Virus 2 (HSV-2) Eradicated in 1979 due to worldwide vaccination campaigns

25 Vaccines Weakened virus or part of pathogen that triggers immune system response

26 Emerging viruses = mutation of existing viruses

27 Genetics of Bacteria Bacterial genome Nucleoid: region in bacterium densely packed with double-stranded DNA (no membrane) Plasmids: small circles of DNA (few to several dozen genes) Reproduction: binary fission (asexual) Creates identical offspring. Spontaneous mutation introduces variation.

28 Restriction Enzymes Natural in bacteria Destroy viral DNA Cut DNA at specific sequences DNA ligase-seals openings created by restriction enzymes.

29 Genetic recombination Transformation: the uptake of naked, foreign DNA from the environment. Transduction: phages that carry bacterial genes from 1 host cell to another. Conjugation: direct transfer of genetic material through a conjugation pilus.

30 Pg. 108 Diagrams-Draw and label these diagrams Fig Lytic and Lysogenic Fig Reproduction of HIV Pg. 109 Article: Hunt for Cures

31 Out 1. Why do many scientists classify viruses as non-living? 2. Draw the basic structure of a virus. Label and define capsid, viral envelope and nucleic acid.

32 Tues. 1/28 Collect: Ch. 14 Guided Reading Today: Quiz-Ch. 20, Finish E. coli Insulin Factory, DNA Tech Chart. Next class: Essay-Ch. 14 or 20 Homework: Experimental Organizer- Transformation Lab-due Mon, Finish DNA Tech Chart.

33 In: pg 110 Watch the clip and write down 10 facts.

34 Pg. 111 DNA Technologies Category Technique Purpose Detailed Description of process Important Vocabulary Associated with Process. Practical Application(s) DNA Cloning Recombinant DNA Technology What does this mean? PCR Gel electrophoresis

35 Recombinant DNA

36 DNA Cloning Using Bacteria Purpose: permits production of multiple copies of a specific gene or produce a specific protein in large quantities. Examples-genes for pest resistance in plants, human insulin production. Description of process Bacterial plasmid and gene of interest isolated Gene inserted into plasmid and put back in bacteria thru transformation. Recombinant bacteria reproduce thru binary fission. Identify clones carrying desired trait. Either transfer genes to new organism or harvest proteins from culture.

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38 Gel electrophoresis

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40 Out A small specimen of blood is retrieved from a crime scene. The crime lab is going to fingerprint the DNA to try to ID the criminal. However, they run the DNA sample through PCR first. Why did they to this?

41 Thurs. 1/30 Today: Essay, Who Ate the Cheese DNA fingerprinting Activity. Next Class: Bacterial Transformation Lab-be ready for lab Mon and Wed. Homework: Finish Who Ate the Cheese and review Bacterial Transformation Lab and complete Experimental Organizer. INB Check Wed of next week.

42 Pg. 112 Ch 14 Guided Reading Pg. 113 The 2 POGIL Biotech assignments.

43 In: pg. 114 Use the Gel Electrophoresis Info Sheet to answer the questions: 1. What is the purpose of a. Gel electrophoresis b. Electric current c. Wells 2. Which direction does DNA move on the gel? Why? 3. How are the different size DNA fragments separated? 4. What are 2 uses of this technology?

44 Pg. 115 Who Ate the Cheese Gel Electrophoresis Lab

45 Out Look at fig on pg According to the gel, Which male is the child s father? Explain.