Escherichia coli (E. coli) is normally found in living intestine of humans and animals. A bacterium that are harmless and is important to the health of the human’s intestinal tract. The intestinal tract is part of the digestive system; having varies of sizes of intestine that transport the food in order to absorb the nutrients and expel the waste. However, some E. coli are pathogenic, causing illness to the host such as diarrhea or harm the outside of the intestinal tract. The host can be effected by the consumption of contaminated water or food, or having contact with the animals or people. Penicillin, is the first antibiotic that is medically used to fight off a large range of bacterial infection. For this experiment, we will be using ampicillin, it is a part of the penicillin drug group. The ampicillin inhibits the bacteria with the result of killing the bacterium or prevents it from multiplying. “When a bacterium multiplies, small holes open up in their cell walls as the daughter cells divide. These holes are then backfilled with newly produced peptidoglycans and the wall is reconstructed (Newman).” …show more content…
Where natural selection occurs when a portion of the population dies off due to the ampicillin, while the rest of the population manage to survive when carrying a resistant gene. As the continuation of survival, the E. coli will develop an immunity against the ampicillin. Making it difficult to eliminate, while it multiplies for a new population of resistant E. coli. When the bacterium become resistant against the antibiotic, patients with the infection will take a longer time to recover to fight off the