The flower is an essential reproductive organ in all flowering plants, especially in angiosperms. Flower is a modified shoot developed for sexual reproduction. Bract is the leaf, from the axil of which a flower develops. A typical flower consists of various parts as illustrated below:
i) Peduncle and thalamus :
A typical flower has a peduncle or stalk. The tip of the peduncle develops into somewhat enlarged structure called thalamus. Thalamus bears other parts of the flower.
ii) Calyx :
It is the outermost accessory whorl of the flower. It is usually green. The units of calyx are called sepals. Sepals are leaf-like. The main function of calyx is to protect the flower in bud condition against a) insects, b) rain, c) drought and d) intense sunlight.
iii) Corolla :
Corolla is the accessory whorl next to calyx. The units of corolla are called petals. Petals are delicate, normally of attractive colours and having sweet smell. Corolla performs the function of attracting insects or other animals for pollination. Corolla also protects the essential whorls of the flower during development. In certain flowers the calyx and corolla are similar in shape and colour and are indistinguishable. The calyx and corolla are together known as perianth e.g., crinum, tuberose etc.
