1. Viruses and Diseases in the Civil War Miss Sabia

2.  Be able to summarize both the lytic and lysogenic cycle.  Be able to compare the structure and characteristics of viruses and bacteria.  Be able to properly perform a swab technique. Objectives

3.  Typhoid  Pneumonia  Measles  Tuberculosis  malaria The Main Killers

4.  Microbes that cause diseases… VIRUSES and BACTERIA Pathogens

5.  Earliest form of life (3 billion years ago)  Prokaryotic cells (no organelles, no nucleus)  Single celled  have a cell wall Bacteria

6.  3 shapes:  Cocci (spherical)  Bacilli (rod shaped)  Spirilla (spirals) Bacteria

7.  Use flagella to “swim” or produce thick coats of slime to “slide” around Bacteria

8.  Give off chemicals called toxins that can make us sick  Our body fights off bacterial infections using antibodies How Bacteria Infect

9.  Single-celled  Not considered living  Cannot reproduce on their own  They are not made up of cells  They cannot respond to the external environment  Cannot move on their own  Called “particles” or “agents”  About 4,000 different types of viruses Viruses

10.  Have genetic material (DNA or RNA) enclosed in a capsid  Some viruses have a viral envelope covering their capsid (taken from host cell)  sneaky Viruses

11.  Lytic cycle  1. entry into cell  2. replicate DNA  3. make viral proteins  4. assemble new generation  5. exit from infected cell—host cell bursts open (lyses) and virus is released into the environment, host cell dies  http://www.youtube.com/watch?v=3DP-MAhr0YY http://www.youtube.com/watch?v=3DP-MAhr0YY How Viruses Infect

12.  Lysogenic cycle (sneaky!)  1. entry into cell  2. DNA incorporated into host cell’s DNA  3. host cell copies chromosomes  4. host cell divides and replicates—all new cells have virus’ DNA incorporated into their own  5. steps 3-5 from lytic cycle  http://wrate.me.vccs.edu/courses/env108/lesson2_4.h tm http://wrate.me.vccs.edu/courses/env108/lesson2_4.h tm How Viruses Infect

13.  Swab Demo:http://www.youtube.com/watch?v=2U6usyE80i ohttp://www.youtube.com/watch?v=2U6usyE80i o  Note: we will not be wetting our swabs in distilled de- ionized water as the video says Microbiology Lab—Microbes Around Us