BIOL 1114 Study Guide - Gram Staining, Amoeba, Crystal Violet

• School: Northeastern University
• Department: Biology
• Course: BIOL 1114
• Professor: Mary- Susan Potts- Santone

Document Summary

Cell wall made of peptidoglycan: composed of sugars, carbs, and amino acids purpose of peptidoglycan is in the cell wall as reinforcement, which protects it from the environment and osmotic pressure changes. Classified through gram positive and gram negative: gram positive - thick peptidoglycan (purple): retains stain, gram negative - thin peptidoglycan (pink) Heterotrophs: need an outside food source for energy ex. ) humans. Symbiotic relationship - is an interaction between 2 or more organisms that may or may not benefit each other. E. coli is found in the intestines of humans and other animals: gram negative light pink color (tint) small dots (rod-shaped) Staphylococcus is a bacteria found on the skin: gram positive purple color grouped together in chains cocci shaped, gram iodide. Order of gram staining technique: crystal violet, decolorizer, safranin. Importance of gram staining differentiating between bacterial species which antibiotic to use if pathogenic. Cyanobacteria (anabaena) cocci in long chains blue color photosynthetic.