2. Biological Resistance (15.2)
State Standard
SB5E. Recognize the role of evolution to biological resistance (pesticide and antibiotic resistance)

3. Bacteria reproduce quickly and their population grows rapidly.
Chapter 15
15.3 Natural Selection-Speciation-Resistance
Antibiotic Resistance
Bacteria reproduce quickly and their population grows rapidly.
Mutations can lead to traits that allow certain individuals to be immune to antibiotics.
These survivors then reproduce quickly (cloning themselves) and establish a population of antibiotic resistant bacteria.

4. Antibiotic Resistance Cont’d
Ch. 15
15.3 Natural Selection-Speciation-Resistance
Antibiotic Resistance Cont’d

5. Ch. 15
15.3 Natural Selection-Speciation-Resistance
Antibiotic Resistance Cont’d
The overuse of antibiotics has caused antiobiotic-resistant populations of bacteria to become a dangerous problem.
Methicillin-resistant Staphylococcus aureus (MRSA) is a bacterium that causes infections in different parts of the body. It's tougher to treat than most strains of staphylococcus aureus -- or staph -- because it's resistant to some commonly used antibiotics

6. Antibiotic Resistance Cont’d
Ch. 15
15.3 Natural Selection-Speciation-Resistance
Antibiotic Resistance Cont’d
Typical appearance of MRSA infection

7. Soon, a whole population of pesticide-resistant insects is thriving.
Ch. 15
15.3 Natural Selection-Speciation-Resistance
Pesticide Resistance
Pesticides may kill most members of an insect population, but variation allows some individuals to be immune to pesticides.
Those who are immune are able to survive and reproduce, passing their immunity trait to the next generation.
Soon, a whole population of pesticide-resistant insects is thriving.

8. Pesticide Resistance Ch. 15
15.3 Natural Selection-Speciation-Resistance
Pesticide Resistance
Overuse of pesticides has allowed more and more resistant populations to develop.