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. Both processes will eventually kill bacteria.

(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