Question

Circinate ptyxis is found in :

• A. Pteris
• B. Dryopteris
• C. Cycas
• D. All of these

Answer 1

The correct option is D All of these

Circinate ptyxis can be defined as the leaf folded during developmental stages. This is the characteristic feature of fern.

Nastic movements are responses of plant parts to stimuli. Circinate ptyxis is found only in fern leaves. When the leaves are young they are coiled like the spring. It is coiled to provide protection to the delicate growing tip of the leaf.

Therefore all the three Pteris, Dryopteris and Cycas have this characteristic.