Question

Study the diagrams given below and answer the following questions:

1. Name the structures shown as X and Y in the figures (A) and (B), respectively.
2. Write the functions performed by the structures X and Y.
3. Name the phenomenon depicted and define it.
4. How do the structures X and Y differ from each other?
5. Give examples of the plants which show the said phenomenon.

Answer 1

1. X - Stem Tendril
   Y - Leaf Tendril
2. Stem and leaf tendrils assist the plant in ascending a support.
3. Thigmotropism.
   The growth movement of plant parts in response to touch stimulus is called thigmotropism.
4. The stem tendril (X) is the terminal outgrowth that facilitates the plant's ascent.
   The leaf tendril (Y) is the entire leaf modified into tendrils to turn around the suitable host.
5. Sweet Pea
   Vines and Cuscuta.