waht do you mean by corolla,androecium,and gynoecium?

Corolla – It is the second whorl of a flower. They are also known as petal and are usually the most colourful part of a flower. They sometimes have fragrances and of various shapes. They are useful to attract insects and birds for pollination.

Androecium – It is the male reproductive part of a flower. It consists of stamens. Stamens are made up of two parts – filamentous anther and granular lobes called pollen grains.

Gynoecium – It is the inner most whorl and the female reproductive part of a flower. It consists of ovary, style and stigma. Ovary is a swollen part which contains ovules. Ovary has a pipe-like extension called style and a flattened tip called stigma. Stigma receives the pollen grains. Ovules are attached to the ovary with a cushion like structure called placenta.