Diseases Caused by Bacteria and Viruses

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
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
Bacteria and Viruses

• Viral Disease in Animals
• Cancer-causing viruses are known as_____.
• oncogenic viruses

14
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
  hosts DNA?
• prophage

16
BACTERIA AND VIRUSES

• What is a rod-shaped bacterium?
• bacillus

17
BACTERIA AND VIRUSES

• What is a compound that blocks the growth and
  reproduction of bacteria?
• antibiotic

18
BACTERIA AND VIRUSES

• What is a virus that infects bacteria?
• bacteriophage

19
BACTERIA AND VIRUSES

• What is a prokaryote that can capture sunlight
  for energy but also needs organic compounds for
  nutrition?
• photoheterotroph

20
BACTERIA AND VIRUSES

• What is the exchange of genetic information that
  occurs from one bacterium to another through a
  hollow bridge?
• conjugation

21
BACTERIA AND VIRUSES

• What is a virus that contains RNA as its genetic
  information?
• retrovirus

22
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