Question

Where do bacteroides occur?
A. Leaves
B. Root nodules
C. Stem
D. Flower

Answer 1

Hint: Bacteroides is a genus of the anaerobic bacteria. These species are mainly non - endospore forming bacilli which may be motile or non - motile. They are found where there is absence of free oxygen.

Complete answer: Bacteroides is the predominant genus which is gram negative. Bacteroides membrane contains sphingolipids. They also contain meso- diaminopimelic acid in their peptidoglycan layer.
lets us infer the options given-
Leaves are usually flattened green outgrowth from the stem. Their main function is photosynthesis and manufacture food for the plants which in turn nourish and provide food to the animals. Oxygen is required for the process of photosynthesis.
Root nodules are usually found in the roots of the plants, usually legumes that form a symbiosis with the nitrogen fixing bacterias. These are formed in the legume plants that are produced because of the infection of the bacteria rhizomes. This free living soil bacteria fixes nitrogen in free condition. The microbe, Frankia, also produces nitrogen fixing nodules on the roots of the non - endospermic plants like Alnus.
Stem is the main structural axis of a vascular plant . It usually supports the leaves, flowers and fruits and helps in the transportation of water and minerals between the roots and the shoots in the xylem and phloem. They are usually herbaceous or woody in nature. Their function is holding the plant parts together.
Flower is a reproductive structure of the plants. They are formed as the result of the reproduction that takes place in the plants. Basically, each flower consists of a floral axis on the area borne the essential organs of the reproduction and usually the non- essential whorls (Sepals and petals) and essential whorls (gynoecium and androecium).

The answer of the above question is option B, Root nodules.

Note: Rhizomes are the bacteria that are present on the root nodules of the leguminous plant. These bacteroides help in the nitrogen fixation. The nodules contain all the necessary biochemical components such as leghemoglobin and nitrogenase enzymes. Plants cannot take up nitrogen directly from the atmosphere. It usually takes place in an anaerobic environment.