Tag: botany

Symbiosis is a type of association of dissimilar organisms of their mutual advantage, e.g., association of nitrogen-fixing bacteria (nodule bacteria) with leguminous roots. The bacteria, inhabiting nodules on roots manufacture compounds from the nitrogen of the air, which becomes available to the plant. From the plant, bacteria obtain carbohydrates and other food materials.

Fungi are also known to form symbiotic relationship with plants (mycorrhiza). Many members of genus glomus forms mycorrhiza.

Bacteroid : Symbiotic bacteria Rhizobium leguminosarum in leguminous plants e.g., gram, pea etc. in their roots nodules produce Leg haemoglobin  this whole Bacteria + Leg haemoglobin + Polyploide  cells of roots is called as bacteroid. 

Nitrogen fixing bacteria are found in the root nodules of leguminous plants. Pea plant being a legume such bacteria would be found in its roots.

Dalbergia is the fast-growing, hardy and surface feeder tap root. They are having a long taproot and numerous surface roots as well. In surface feeders, the taproot does not grow or develop to a great extent.

The cymose or surface feeder tap root systems of some annual plants are consisting of thin fibrous roots. Therefore, also called a fibrous tap root system.

The correct option is A.

Modified adventitious roots, which become green colour and perform photosynthesis. These are called as assimilatory roots, for example, Taeniophyllum, Trapa, Tinospora cordifolia. Tinospora is having climbing photosynthetic roots and is aerial. These are like the green hanging threads developing from the nodes during the rainy seasons.

The correct answers are A and B both. 

Allelopathy is a phenomenon associated with plants, in which one plant produce some chemical substances, which inhibits the growth of other plant species. While, in ammensalism, one species suffer and other remain unaffected.