Question

Give examples for chasmogamous flowers.

Answer 1

The unique feature of chasmogamous flowers is that they have open petals with open reproductive parts. When chasmogamous flowers reach maturity, they un-whorl and their stamens and style are made available for pollination. Although some of the chasmogamous flowers self-pollinate, most chasmogamous flowers are cross-pollinated with the help of biotic and non-biotic agents.

Complete explanation:
Chasmogamous flowers belong to angiosperms. Some of the chasmogamous flowers include sunflower, Hibiscus , Viola , beans, peas and commelina flowers.
Chasmogamy is a type of pollination that occurs only in chasmogamous flowers. In this type of pollination, the flowers open their floral parts including anthers and stigma for pollination to take place.
Most chasmogamous flowers are bisexual and shows cross pollination. However, self-pollinating chasmogamous flowers are also present. For cross pollination to take place, chasmogamous flowers require abiotic and biotic pollinators. The abiotic pollinators include wind, rain, water stream etc. The biotic pollinators are small insects, wasps, butterflies and bees. The seeds produced by chasmogamous flowers are genetically distinct. Hence, these flowers help in increasing the genetic diversity of the population. It also reduces the effects of recessive alleles.

Note:
Any flower that has open petals and reproductive parts are said to be chasmogamous flowers. Another type of flower is the Cleistogamous flowers. Here the flower and the flower buds are unopened. Since they remain closed, forced self-pollination and fertilization occur. These flowers do not need any pollinators. Due to self-pollination, there is no great variation and can pass the recessive alleles to generation after generation. Examples of cleistogamous flowers include Oxalis , Cardamine and pansy.