Question

What is another name for multicostate venation?

Answer 1

Hint: Multicostate venation is a type of reticulate venation that is seen in leaves. It can be seen in plants such as castor, ziziphus etc.

Complete answer:
The arrangement of veins and veinlets on the lamina of a leaf is called venation. Veins and veinlets help in conduction. They are visible on the surface of lamina, especially the under surface in dorsiventral leaves. Their important functions are:
(a) Conduction of water through xylem.
(b) Providing channels for translocation of organic nutrients,
(c) Conduction of minerals.
Venation is of three main types-reticulate, parallel and furcate.
Reticulate Venation-In this type the veinlets from a reticulum or network. It is found in dicots. It is of two type:
(A)-Pinnate or unicostate reticulate venation. The lamina has a single principle vein or midrib which extends from its base to apex. It gives rise to lateral veins along its entire length like the plumes of a feather.
(B)-Palmate or multicostate reticulate venation. A number of prominent or principal veins arise from the tip of the petiole and reach either apex or margins of lamina. They give rise to lateral veins connected by reticulation of veinlets. It is of two type, which are:
(I) CONVERGENT- It is a type of venation in which principal veins converge towards the apex of the lamina. Example- ziziphus, Smilax.
(II) DIVERGENT- It is the type of venation in which the principal veins diverge towards the margin. Example- luffa, Ricinus.
Multicostate venation is also known as palmate reticulate venation.

Note:
The design and function of leaf venation are an important aspect to know how a plant performs its functions. They are a key to distribution and production in the ecosystem. The number of veins and veinlets on the surface of the leaf helps in knowing the climate, habitat and growth form worldwide.