Viruses and Diseases in the Civil War

Miss Sabia

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

Typhoid Pneumonia Measles Tuberculosis malaria

The Main Killers

Microbes that cause diseases…

VIRUSES and BACTERIA

Pathogens

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

Bacteria

3 shapes: Cocci (spherical) Bacilli (rod shaped) Spirilla (spirals)

Bacteria

Use flagella to “swim” or produce thick coats of slime to “slide” around

Bacteria

Give off chemicals called toxins that can make us sick

Our body fights off bacterial infections using antibodies

How Bacteria Infect

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

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

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

How Viruses Infect

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.htm

How Viruses Infect

Swab Demo:http://www.youtube.com/watch?v=2U6usyE80io Note: we will not be wetting our swabs in

distilled de-ionized water as the video says

Microbiology Lab—Microbes Around Us