Question

Difference between stem tendril and leaf tendril

Answer 1

A tendril in botany is a specialized stem, leaves or petiole that is threadlike in shape and is utilized by climbing plants for support, attachment and cellular invasion by parasitic plants. Tendrils don't have lamina or blade but are able to carry out photosynthesis. 

In a stem tendril the terminal bud is modified to be tendrils where the growth occurs with the help of axillary bud. This helps the plant body to climb e.g Grape vine and Passion fruit

On the other hand, 

In a leaf tendril the entire leaf is modified into a tendril this helps in climbing plants or twining around suitable host. The leaf tendril helps a vining plant to secure itself through possessing a twining growth habit

Answer 2

Tendrils are a specialized part of a plant, which are slender, thread-like strands that help in supporting vining stems. Tendrils can be formed from modified leaves, leaf tips, leaflets, or stipules.

The anatomy of the tendrils may be either the leaf-stalk tissue or the stem tissue.

Stem tendrils – Stems or branches of stems are modified into green-colored thread like structures called tendris. They are leaf-less structures and help in climbing. There is always a scale leaf at the point where the tendril branches.

There are 4 types of Stem tendrils – Axillary (Passiflora), Extra-axillary (Cucurbita), Apical bud tendrils (Grapevine), and Inflorescence tendrils (Cardiospermum).

Leaf Tendrils – In plants with weak stems, the leaves or a part of the leaves get modified into structures that are green-colored and thread-like called tendrils. They help the plant in climbing around a support.

There are different types of leaf tendrils depending on the part of the leaf that is modified to become a tendril. Entire leaf (Lathyrus aphaca), Upper Leaflets (Pisum sativum), Terminal leaflets (Naravelia), Leaf Tip (Gloriosa), Petiole (Clematis) and Stipule (Smilax).