1. Section 31-1 “Pathogens and illness”

2. State Standards
10. Organisms have a variety of mechanisms to combat disease. As a basis for under-standing the human immune response:
C. Students know there are important differences between bacteria and viruses with respect to their requirements for growth and replication, the body's primary defenses against bacterial and viral infections, and effective treatments of these infections.

3. KEY CONCEPT: Germs cause many diseases in humans

4. The Germ theory says that microorganisms cause diseases
proposed by Louis Pasteur
led to rapid advances in understanding disease

5. Koch’s postulates support the theory
Disease-causing agents are called pathogens

6. What does the root word “path” mean?
Feeling or suffering
Examples: sympathy, apathy, empathy, telepathy, pathology
Pathology is the study of diseases (sicknesses)
Pathogen is anything causing disease

7. There are different types of pathogens.
Bacteria are single-celled organisms
cause illness by destroying cells
release toxic chemicals
Example: staph, strep throat

8. Viruses are genetic material (DNA) surrounded by a
protein coat
force host cells to make more viruses
very small
Example: flu, rhinovirus (rhin= nose; common cold), HIV

9. Fungi can be multicellular or single-celled
take nutrients from host cells
occur in warm and damp places
Example: athlete’s foot, yeast infections

10. Protozoa are single-celled organisms
use host cells to complete their life cycles
take nutrients from host cell
Example: malaria

11. Parasites are multicellular organisms
grow and feed on a host
possibly kill the host
Example: tapeworm

12. Different pathogen cause common infectious diseases.

13. Pathogens can enter the body in different ways
Pathogens can be transferred by direct or indirect contact
Indirect contact does not require touching an infected individual
touching an infected surface
breathing in infected air

14. Vectors carry a pathogen and transmit it into healthy cells
Direct contact requires touching an infected individual
Includes:
kissing
sexual intercourse
hand shaking
tick