Question

Describe the structure of a typical flower.

Answer 1

Different parts of a typical flower are described below:
Bract:
Below the base of a flower a scaly leaf like structure present is know as bract. A bract acts like an umbrella and protects the flower in bud condition from severe climatic conditions. A flower with bract is known as bracteate flower and without it is known as ebracteate flower. In Bougainvillea and Poinsettia plants, the flowers are provided with enlarged colorful bracts to attract insects for pollination.

Pedicel:
A stalk like structure which connects a flower to the stem is known as pedicel. A flower with pedicel is known as pedicillate flower and the one which is directly attached to the stem without pedicel is known as sessile flower.

Thalamus:
Thalamus or receptacle is a swollen or flat or dome-shaped or concave structure present at the tip of the pedicel. Thalamus is the structure on which all the floral parts arise or attached.

The floral parts of a flower are arranged on the thalamus in a ring like fashion called whorls. Usually there are four whorls of floral parts present in a typical flower. These whorls from outside of a flower to inside are Calyx (sepals), Corolla (petals), Androecium (stamens) and Gynoecium (carpels). Calyx and Corolla are known as non-essential whorls of a flower as they are directly involved in the process of reduction. Hence they are also known as the accessory organs of the flower. But Androecium and Gynoecium are known as essential whorls of the flower as they are directly involved in the sexual reproduction of the flower.

Calyx:
Calyx is the outermost and first whorl of the flower. The individual members of calyx are known as sepals and are green in color.

Corolla:
Corolla is the second whorl of a flower and the individual members of corolla are known as petals. The petals are differently colored with various colors and shades.

Androecium:
Androecium is the male reproductive part of a flower. It is the third whorl of a flower and the individual members of androecium are known as stamens. Each stamen is comprised of a long filament, a fertile anther and a connective.

Gynoecium:
Gynoecium is the innermost whorl and female part of a flower. The individual members of gynoecium are known as carpels.