Question

What is a flower? Describe the parts of a typical angiospermic flower.

Answer 1

Hint: As flowers help in reproduction in plants. They are also a modified part of the plant to carry out the process of reproduction. A typical angiospermic flower has four parts, which plays an important part in reproduction.

Complete answer:
A flower can be defined as the reproductive unit of any angiosperms. Flowers carry out sexual reproduction in angiosperms. A typical flower is generally an attractively modified stem with a condensed axis.

A flower has four different parts, they are - calyx, corolla, androecium, and gynoecium. The parts androecium and gynoecium contain the male and female reproductive organs of a flower respectively.

The parts of typical angiospermic flowers are as follows-
> Calyx- The calyx is the outermost whorl of a flower. They mainly contain sepals. They are green, and leaf like structures that cover and protect the flowers during the initial stage or bud stage. When the arrangement of sepals in a flower are free, then they are called polysepalous, while when fused are called gamosepalous.

> Corolla- The corolla of a flower is a layer that is found inside the calyx. It contains beautifully and attractively coloured petals. These petals help in alluring and attracting insects for pollination. When the petals in a flower are free, they are called polypetalous flowers, while the flower with fused petals are called as gamopetalous flower.

> Androecium- It is the next part or whorl present after corolla. The androecium typically consists of stamens, which are the male reproductive unit of a flower and is composed of two parts - anther and filament. The anther is the bilobed structure with a stalk called filament. Inside the anther, pollen grains are formed, which are transferred to another plant by pollination.

> Gynoecium- The gynoecium is the innermost part or whorl of a flower. It consists of pistils, which are the female reproductive organs of flowers. A pistil is composed of three parts: stigma, style and ovary.

Note: The number of sepals and petals varies depending on whether the plant is a monocot or dicot. In monocots, the number of petals is usually three or multiples of three whereas in dicots, the number of petals is four or more. The calyx and corolla together are known as the perianth. The third whorl contains the male reproductive structures and is known as the androecium. If all the four whorls are present in a flower, the flower is described as complete, while if any of these four parts is missing, the flower is known as incomplete.
There are flowers that also contain both an androecium and a gynoecium, they are called perfect, androgynous or hermaphrodites flowers.