Question

Cleistogamous flowers are

• A. Bisexual flowers which remain opened
• B. Bisexual flowers which remain closed
• C. Open female flower
• D. Open male flower

Answer 1

Answer: (B)

Bisexual flowers which remain closed

Answer 2

Some plants such as Viola (common pansy), Oxalis and Commelina produce two types of flowers: chasmogamous flowers which are similar to flowers
of other species with exposed anthers and stigma, and cleistogamous flowers which do not open at all. In such flowers the anthers and stigma lie close to each other. When anthers dehisce in the flower buds, pollen grains
come in contact with the stigma to affect pollination. Thus, cleistogamous flowers are invariably autogamous as there is no chance of cross-pollen landing on the stigma. Cleistogamous flowers produce assured seed-set even in the absence of pollinators.