Question

Which of the following statements are correct?

(i) If the stem is jointed with solid nodes and hollow intemodes, it is called caudex.
(ii) In Tridax, the stem is decumbent.
(iii) Corm is a condensed form of rhizome growing more or less in vertical direction.
(iv) Sucker is an underground modificaton of stem.
(v) Biparous type of cymose branching is seen in Saraca.

• A. (i), (iv) and (v)
• B. (ii) and (iii)
• C. (ii), (iii) and (v)
• D. (iii) and (iv)

Answer 1

The correct option is B (ii) and (iii)

Tridax is the plant which is present in the family of daisy. They have simple leaves and are usually annual herbs. They have a decumbent stem. The decumbent stem is the stem in which the stem usually lies on the ground and the tip of the stem faces upward in the direction.

The corm is similar to the rhizome. The rhizome is the swollen stem which grows in the horizontal direction. The corm grows in the vertical direction making them somewhat similar to each other.

The unbranched stem is called caudex or columnar, e.g., Palm, Sugarcane, Maize. The stem that has hollow internodes and solid prominent nodes is called culm.

In the decumbent stem, the stem grows for some distance on the ground and then tries to grow upward at the tip. For example Tridax has a decumbent type of stem. The corm is a thick, large, fleshy underground stem. This is a condensed form of rhizome growing in a vertical direction.The sucker is the modified part of the stem and not the root. In biparous cymose branching, two lateral axes develop at a time e.g., in Mirabilis, Viscum, Stellaria, etc. In Saraca branching is of uniparous type.

Thus, the correct answer is option B.