DNA 2/2/16 What are some viruses that you have heard of? What are some ways that you can catch viruses from people or other animals? What measures do we have in medicine to fight viruses?

Announcements Case Study Group deliverables have been graded! RESUBMISSION RULES: (Warning-- any resubmissions that do not follow the following format will not be graded.) Resubmissions must be completed and submitted INDIVIDUALLY. Use google doc’s “Make a copy” function. Then, edit/ add to the group doc you turned in INDIVIDUALLY. Write all corrections and additions IN RED. Turn resubmissions in to turnitin.com by Mon 2/8 at 11:59 PM. Title your document “Lastname_firstinitial_resubD1” for the chart and “Lastname_firstinitial_resubD2” for the paragraphs. Example: “Chase_L_resubD1”

Announcements EKS 2 “Building Blocks of Life” Unit Assessment Tues 2/9 (you will receive study guide today!) Rough draft of data and analysis section due tomorrow in class! Case Study video due this Thurs at 11:59 PM (upload to youtube, and paste your youtube link into the turnitin.com assignment) Final draft of Farmville lab report due to turnitin on Mon 2/8 at 11:59 PM.

Simulating the spread of viral infections… Some of you have been infected with a virus! Oh no! You are a naïve, promiscuous college student, and exchange “body fluids” with 3 people each. Let’s see how quickly the virus spreads… How many people do you think will be infected by the end?

Viral transmission demonstrates Exponential growth Number of people infected by Virus X every day Number of days Number of infections This is why we say popular youtube videos “went viral!” It means they grew popular really quickly!

What are viruses? Viruses are small infectious agents that can only replicate inside the cells of living organisms

Viral anatomy Viruses are mainly made up of two parts: 1) Nucleic acids (either DNA or RNA) 2) A protein coat ( capsid ) They can sometimes have a viral envelope

Viruses vs Cells Viruses are NOT considered cells because: 1) They need hosts to survive 2) They do not have all the components that cells have: cell membranes, cytoplasm, DNA, ribosomes

Structural comparison between virus and animal cell Viruses are extremely small (much smaller than animal cells) 0.25  m Virus Animal cell Bacterium Animal cell nucleus

Bacteriophages Viruses that infect bacteria are called Bacteriophages, or just Phages *used to treat bacterial infections prior to the discovery of antibiotics!

Activity: How do viruses infect cells? With a partner, try to organize the pathways into a logical order that demonstrate the infection pathway of viruses

How are viruses able to reproduce so rapidly!?

There are two main infection strategies Lytic cycle: makes many new phages and results in the death of the host cell Lysogenic cycle: replicates the phage DNA without destroying the host cell

How are viruses significant in our lives? Chicken Pox Ebola Common Cold Influenza Rabies