Microbial Nutrition And Growth Flashcards
Organisms use a variety of chemicals called nutrients to meet their energy needs and to build organic molecules and cellular structure the most common of these nutrients are compounds containing necessary elements such as
Carbon, oxygen, nitrogen, and hydrogen
define autotrophs
Organisms that utilize and in the organic source of carbon as their sole source of carbon
Define heterotrophs
Cataba lies reduced organic molecules such as proteins they acquire from other organisms
Define phototrophs
Organisms that use light as their energy source
Define chemotrophs
Organisms that acquire energy from redox reaction including inorganic and organic chemicals
Define Organotrophs
Hetero trough’s acquire electrons from the same organic molecules that provide them carbon
Define lithotrophs
Autotrophic organisms acquire electrons or hydrogen atoms from inorganic molecules
Obligate aerobes
Oxygen is essential because it serves as the final electronic scepter of electron transport chain which produced most of the ATP in these organisms
Obligate anaerobes
Cannot use oxygen to produce ATP
Singlet oxygen
Is molecular oxygen with electrons that have been posted to a higher energy state typically during aerobic metabolism
Superoxide radical (O2-)
A few superoxide radicals form during the incomplete reduction of 002 during electron transport in aerobes and during metabolism by anaerobes in the presence of oxygen
Peroxide anion
Hydrogen peroxide form during reactions catalyzed by super oxide dismutase contains peroxide and ion another highly reactive oxidant
Nitrogen
Is often a growth limiting nutrient for many organisms that is their anabolism seizes because they do not have sufficient nitrogen to build proteins and nucleotides
Nitrogen fixation
As essential for life on earth because nitrogen fixers provide nitrogen in a usable form two other organisms
Psychrophiles
Grow best at temperatures below about 15°C and can even continue to grow at temperatures below 0°C
