Question

What is the function of circinate vernation? Thank you!

Answer 1

Answer:

By photosynthesizing, the frond increases the amount of solute inside the frond, which lowers the internal water gradient and facilitates an increase in volume that forces uncoiling. In the case of many fronds, long hairs or scales provide additional protection to the growing tips before they are fully uncoiled.

Answer 2

Vernation –spring bud break  

Circinate – coiled leaf arrangement in the bud.

The function is a growth pattern; meristem produces a leaf promordia with cells spaced in a spiral. With cell growth the leaf forces itself to unfold.

Fern leaves emerge in spring from a coil. The inner cells take up water and expand as they begin to grow, forcing the coil to unfold. The older outer layers of the coil, which toughen and begin photosynthesizing once exposed, protect the central meristem. This photosynthesis supports the meristem for further growth and expansion of the coil forcing it to open further. Some fronds also have hairs or scales that protect the tender growing coil.