1. Diseases Caused by Bacteria and Viruses
Section 19-3
This section describes bacterial and viral diseases.

2. Bacterial Disease in Humans
What are pathogens?
They are disease-causing agents.

3. Bacterial Disease in Humans
What are the two general ways that bacteria cause disease?
Some damage the tissues of the infected organism directly by breaking them down for food.
Others release toxins that harm the body.

4. Bacterial Disease in Humans
What kind of tissue do the bacteria that cause tuberculosis break down?
They break down lung tissue.

5. Bacterial Disease in Humans
What are antibiotics?
They are compounds that block the growth and reproduction of bacteria.

6. Bacterial Disease in Humans
What is one of the major reasons for the dramatic increase in life expectancy during the past two centuries?
There is an increased understanding of how to prevent and cure bacterial infections.

7. Controlling Bacteria What is sterilization?
It is a way of destroying all bacteria by subjecting them to great heat.

8. disinfectant Controlling Bacteria
A chemical solution that kills pathogenic bacteria is called a(an) _____.
disinfectant

9. Controlling Bacteria
Why will food stored at low temperatures keep longer?
The bacteria in the food will take much longer to multiply.

10. Controlling Bacteria How can food be preserved through canning?
This method involves heating food to a high temperature and then immediately placing it into sterile glass jars or metal cans and sealing the container.

11. Controlling Bacteria
What everyday chemicals can be used to inhibit the growth of bacteria in food?
They include salt, vinegar, and sugar.

12. Viral Disease in Humans
What are some human diseases that viruses cause?
Viruses cause polio, measles, aids, mumps, influenza, yellow fever, smallpox, the common cold, and many other diseases.

13. oncogenic viruses Bacteria and Viruses Viral Disease in Animals
Cancer-causing viruses are known as_____.
oncogenic viruses

14. prion Bacteria and Viruses Viroids and Prions
A disease-causing particle that contains only protein and not DNA or RNA is called a(an)_____.
prion

15. WordWise
What is the viral DNA that is embedded in a host’s DNA?
prophage

16. BACTERIA AND VIRUSES
What is a rod-shaped bacterium?
bacillus

17. antibiotic BACTERIA AND VIRUSES
What is a compound that blocks the growth and reproduction of bacteria?
antibiotic

18. bacteriophage BACTERIA AND VIRUSES
What is a virus that infects bacteria?
bacteriophage

19. photoheterotroph BACTERIA AND VIRUSES
What is a prokaryote that can capture sunlight for energy but also needs organic compounds for nutrition?
photoheterotroph

20. conjugation BACTERIA AND VIRUSES
What is the exchange of genetic information that occurs from one bacterium to another through a hollow bridge?
conjugation

21. retrovirus BACTERIA AND VIRUSES
What is a virus that contains RNA as its genetic information?
retrovirus

22. nitrogen fixation BACTERIA AND VIRUSES
What is the process in which nitrogen is converted into a form plants can use?
nitrogen fixation

23. BACTERIA AND VIRUSES Hidden Word: pathogen
Definition: A disease-causing agent