micro ch 15
Card Set Information
micro ch 15
opinion of atmospheric nitrogen essential for plant growth;
bacteria from nodules
importance of nitrogen metabolism
N - essential element of organic compounds, including amino acids
trapping of nitrogen gas from atmosphere and its incorporation in organic compounds
two types of microbes accomplishes nitrogen fixation.
free living nitrogen fixers includes these species.
Azotobacter, Beijerinckia, & Clostridum
and cyanobacteria (
Nostoc & Anabaena
symbiotic nitrogen-fixers includes these species.
-live in nodules on roots of legume plants
symbiotic relationship between microbes and plants...
complex; involves chemical attraction between bacterium and cells of plant root, binding to plant root, curling and branching of rootlets, and entry of bacteria into root hairs
-infection thread develops and tumorlike growth (nodule) and bacter aumme distorted forms (bacteriods)
bacteria that's distorted form in the nodules
Bacteria that started a symbiotic relationship...
cannot live independently
ammonia deposited in soil and converted to valuable nitrate ions thru this process
steps of nitrification
, convert ammonia to nitrite ions
2. nitrite ions converted by
to nitrate ions, which are relished by plants for making their organic materials
nitrification occurs under ..
aerobic conditions and used by microbes as energy-yielding process
some species of microbes break down nitrate ions and produce nitrogen gas, giving atmosphere
Cheese manufactured from milk in 3 steps.
1. curd formation
2. curd treatment
3. curd ripening
a bacterial insecticides
type of virus having high affinity for insect tissues.
-gene cloned from cells of scorpion which have toxin that paralyzes larvae of moths.