BIOL 2051 Chapter : Micro Chapter 5
Document Summary
Chapter 5 - environmental influences and control of microbial growth. Environmental factors that affect microbial growth: temperature, pressure, osmolarity (salt or sugar concentrations, ph, oxygen. Extreme thermophiles: 65 c 113 c, psychrophiles -- found in constantly cold environments. Found in warm-blooded animals & many terrestrial & aquatic environments. Examples- most organisms you are familiar with such as escherichia coli (found in the human intestine) Thermophiles: optimum temp above 40 c, places thermophiles are found: Some archaea have been found growing at temps above 110 c soils subjected to full sunlight fermenting materials (compost piles: hot springs. Thermus aquaticus is a common hot spring thermophile. Emergency proteins produced: help keep proteins from denaturing. Induced by many stressful conditions: heat, high salt concentrations, arid conditions. Pressure: barophiles, adapted to high pressures, up to 1,000 atm, barotolerant organisms, grow athigh, but not very high pressure, barosensitive organisms, die at high pressure, most typical bacteria, all mammals.
