differentiate between Phyllotaxy and venation.
Answers
Explanation:
Phyllotaxy is the arrangement of leaves on the stem of a plant. It is of three types — alternate, opposite and whorled. venation is the arrangement of veins on a leaf. It is of two types — parallel and reticulate.
Reticulate venation:
This type of venation is a characteristic feature of the leaves of the dicotyledons plants. A number of lateral veins are developed from the midrib and give rise to many veinlets. The lateral veins and veinlets form a network of reticulum in the lamina and for this reason, such a venation is called reticulate venation. Reticulate venation may be of the following two types:
venation
Unicostate or pinnate:
When there is only one prominent midrib, from which the lateral veins are developed, the venation is known as uicostate reticulate or pinnately reticulate. Examples, mango, sunflower, guava.
Multicostate or palmate:
When a number of prominent veins enter into the lamina from the petiole and spread out like the fingers of the palm, the venation is known multicostate reticulate or palmately reticulate venation.
Phyllotaxy:
The mode of arrangement of leaves on the stem or branch is known as phyllotaxy. By means of various types of arrangements the leaves avoid shading over one another and get themselves better exposed to sunlight, so that they can carry out the function of synthesis of food. Mainly there are two types of phyllotaxy – spiral and cyclic.