Hydrangea Plant

SEXUAL REPRODUCTION IN FLOWERING PLANTS

FOR EXERCISE QUESTIONS AND SOLUTIONS

Flower – A Fascinating Organ of Angiosperm

  • Flower is a sexual reproductive part of angiosperms. It develops after the completion of vegetative phase.

  • The branch of ornamental horticulture concerned with growing and marketing of ornamental flowers is called floriculture.

 

Parts of Flower

  • Flower has four different sets of whorls or floral members are attached to a central axis called thalamus.

  • The outermost and the first accessory whorl is of sepals and is called calyx.

  • The second accessory whorl is of petals and is called corolla.

  • Next to the corolla, is the male reproductive whorl of stamens called androecium.

  • The innermost female reproductive whorl is of carpels and is called gynoecium or pistil.

 

Functions of Floral Members

Calyx

  1. Its main function is to protect the flower in bud condition, it is smaller than the petals in size.

  2. When green, it is photosynthetic in nature.

  3. When coloured, it attracts insects for pollination.

 

Corolla

  1. It is a bright coloured attractive part of a flower and has scent to attract pollinators.

  2. Sometimes the base of corolla bears some secretory glands (nectariferous gland) and secretes nectar.

  3. They also provide protection to the plant.

 

Androecium

Its main function is the production of microspores, i.e., pollen grains containing male gametes within the anther lobe.

 

Gynoecium

The function of gynoecium is the production of megaspores, fruits and seeds.