UNIT 7 NOTES ANTIBIOTIC RESISTANCE EVOLUTION 1 ADDIES

UNIT 7 NOTES: ANTIBIOTIC RESISTANCE & EVOLUTION

(1) ADDIE’S CASE: • Contracted a bacterial infection. • The infection developed very fast and spread throughout her whole body. • They initially treated her with medication for pneumonia, but she did not have this. • The bacteria she was left with were all resistant to antibiotics and could not be treated.

(2) MRSA: • MRSA refers to bacteria which are resistant to multiple types of antibiotics, and cannot be treated.

(3) ANTIBIOTICS : • MRSA and Antibiotic Resistance also develops because: – Some bacteria naturally have genes that allow them to survive antibiotics. – We overuse antibiotics. – We do not properly use antibiotics. – Bacteria can exchange resistant genes. • Antibiotics work by: – Preventing bacteria from producing proteins and reproducing. – Breaking down bacteria cell walls.

(4) MRSA GRAPH: • The number of resistant bacteria are increasing every year. • Bacterial resistance begins in places like hospitals, and spreads out into the community.

(5) LAB PURPOSE & RESULTS: • The Purpose: See which areas of the school had higher amounts of bacteria, and which areas had lower amounts. • The Results: – Bacteria were not visible initially because they are so small. – Over time we were able to see colonies of bacteria because they grew and multiplied using mitosis. – Areas with high traffic and usage, moisture, and textured surfaces collected larger amounts of bacteria. – Areas with low traffic, which were dry, and had smooth surfaces collected smaller amounts of bacteria.

(6) EVOLUTION: • Evolution is the change in the types of traits that show up in a population, over time. • Evolution is driven by: – Population growth. – Population diversity. – Competition for resources. – Survival of only some organisms.

(7) NATURAL SELECTION: • Natural Selection is the survival of better adapted organisms, and the removal of “weaker” or poorly adapted organisms. • “Survival of the Fittest” • In order for Natural Selection to drive a population to evolve and change, there needs to be: – Diversity – Competition