Rhizobium bacterium
lab: examine root nodules from clover plants under the dissecting microscope and also examine prepared slides of rhizobium under the light microscope. Clover plants can be sampled from the garden and your teacher will look in the slide collection in the back room to see if the rhizobium slides are there. if not, you will observe these when I return next week. --S.N.
We know that plants are important to the ecosystem because they photosynthesize. Did you know that some plants are legumes and these are special because they have ROOT NODULES which are nitrogen fixers. These root nodules are little rooms where Rhizobium bacteria convert nitrogen gas into ammonium and then Nitrobacter bacterium in the soil converts ammonium into nitrates. Plants can absorb nitrates to make plant protein. When those plants are eaten by animals, then animals use the nitrogen to make animal protein. You can say that all the protein on your body (muscles, enzymes, hair, fingernail etc) was built from nitrogen which was fixed by Rhizobium at some point in time.
10 points
Only certain plants contain these root nodules...amongst them are bean plants and clover plants. Look at the roots of clover and draw a picture of root nodules.
