Question

The correct sequence of events in nodule formation is:

• A. Curling of root hairs - rapid division of cortical cells - production of infection thread - bacteria enters polyploidy cells - colonization of surrounding areas of roots
• B. Rapid division of cortical cells - production of infection thread - curling of root hairs - colonization of surrounding areas of roots - bacteria enters polyploidy cells
• C. Colonization of surrounding areas of roots - curling of root hairs - production of infection thread - rapid division of cortical cells - bacteria enters polyploidy cells
• D. Colonization of surrounding areas of roots - rapid division of cortical cells - bacteria enters polyploidy cells - curling of root hairs - production of infection thread

Answer 1

The correct option is C

Colonization of surrounding areas of roots - curling of root hairs - production of infection thread - rapid division of cortical cells - bacteria enters polyploidy cells

Nodule formation begins with colonization of the surrounding areas of the root by the bacteria, followed by curling of root hairs due to the nod factors released by the bacteria. An infection thread is then produced to carry the bacteria inside the cortex of the root, which stimulates rapid cell division and finally the bacteria enters only the polyploidy cell which then forms nodules.