1. Essential Question: Why aren’t viruses considered to be alive? Science 7

2. Next Science Test: “Micro-Organisms and Germ Theory of Disease” Unit Test (QUARTERLY) Friday, January 22 Study guide is also posted online

3. Homework: Science I recommend completing SLIDE 10 from your unit review slides this evening Unit Review Slides are due on Friday, January 22

4. POSTER: Compare the four kinds of protists we have looked at. For each do all of the below: (10 minutes) A picture of each organism (labeled with major organelles!) Identify as protozoa or algae Identify whether it is a producer or consumer Describe how it moves Describe how it eats Identify one similarity it shares with the other three protists Identify one unique feature that none of the other three have in common with it.

5. Today’s Topic: Why aren’t VIRUSES considered to be living things?

6. Characteristics of Living Things: Vocabulary There are seven characteristics that all living things share with one another: All living things RESPIRATE All living things EXCRETE waste All living things require NUTRIENTS All living things GROW All living things REPRODUCE All living things are SENSITIVE to their environment All living things MOVE

7. Viruses: Notes Viruses are tiny bits of DNA, wrapped in a protein shell. However, they do not meet several of the characteristics of life: Viruses are not made of cells, they are much, much tinier than a single cell Viruses do not require nutrients in order to survive, because they have no life processes Viruses cannot reproduce on their own Viruses do not respond to their environment Viruses do not respirate, excrete waste, or grow

8. Viral Reproduction: Viruses cannot reproduce on their own, but they do reproduce by infecting host cells Host cell- a cell that has been infected by a virus; steps of a viral infection are listed below Virus attaches to host cell Virus injects its DNA into the host cell Viral DNA rewrites the DNA of the host cell Host Cell begins to assemble more viruses (think virus factory) Host Cell bursts, releasing thousands of copies of the virus

9. Exit Ticket Passcode: “fall” Access the “Exit Tickets” page of DeBolt’s wiki Click on the link for today’s exit ticket Complete the quiz before leaving class Name format: “your period number, Last name, First name”