Circinate Vernation in ferns refers to A. Uncoiling of new leaves from the base towards the apex B. System of leaf gaps in the stems C. Arrangement of son on the leaf surface D. Presence of adventitious root on the rhizome
Hint: Vernation is the process of formation of the new leaves which occurs in different manner in different plants.
Complete answer: Circinate vernation is the type of vernation in which the new leaves emerges in ferns by unrolling from the tight coil. The coiled frond which emerges at first is known as crozier which helps in the protection of tender tips of leaves. The lower parts of frond support the growth and expansion of the frond. Vernation is the term used for the formation of new leaves in small plants (fronds). In circinate vernation there are the leaves in the form of Buds and are enclosed in a protective sheath further they are coiled properly so that the tip of the developing part of the plant should remain secured within it. As the plant becomes mature the coiling starts getting uncoiled itself and the sheath gets opened. Circinate vernation is a type in which the leaf is folded vernation is the growth that a plant is going through. Most fronds don’t have simple leaves. The fronds also help in the process of photosynthesis. The protruding and coiled frond is termed to be fiddlehead. The ferns belong to the kingdom plantae and phylum pteridophyta. There are in total 20,000 species of plants and they have xylem and phloem in them thus called as vascular plants.
The correct answer is (A) uncoiling of new leaves from the base towards the apex.
Note: The leaves of the ferns are different from the true leaves which are present in the flowering plants in its vernation or expansion of leaves from the buds