Flower

Flower

Definition of Flower

The reproductive organ of the flowering plant

More About Flower

• They are observed in the angiosperm plants, i.e the flowering plants
• The structure of the flower consists of four whorls
• They are
  • Calyx:
  • It is the outermost whorl and formed of the units called sepal
    It is a little leaf like part, which covers and protects the flower
    They are generally green and enclose the entire flower right from the bud stage
    They may be absent in some flowers or be prominent in others
    The shape, size, number and colour of the sepals varies accordingly with the species
    The main function of the sepals is to protect and support the flower when it opens
  
  
  • Corolla:
  • This whorl is found inner next to the Calyx
    It consists of units known as petals
    Petals are thin, soft, modified leaves that constitute the most colourful whorl
    The colour of the petals helps in the process of pollination, by attracting insects
    Sometimes the sepals and the petals look similar, in such case, they are known as ‘tepals’
    Examplesof flower having tepals are ‘Tulips and Lilies’

• Androecium:
  This whorl is inner next to corolla
  The units of androecium are called stamen
  They are the’ male reproductive organs’ of the flower
  The stamen consists of a stalk known as filament and an anther
  Pollen grains are produced on the anther
• Gynoecium:
  The innermost whorl, inner next to androecium of the flower is called Gynoecium
  It is a ‘female reproductive part’ and is also referred to as pistil
  The carpel is the unit of gynoecium, and it may be single or many in numbers
  A carpel consists for stigma, style and ovary
  Stigma is the sticky end that receives the pollen and the style is the pathway for the growth ofpollen tube towards the ovary
  The ovules are produced in the ovary
  The fertilisation occurs with the fusion of pronucleus of the male gamete, i.e the pollen grain and the pronucleus of the female gamete i.e the ovary leading to the formation of the fruit and ovules become seeds
  A structure of the flower is represented by floral formula which has specific letters, numbers and symbols 

Questions based on the flower:

1) Which among the following is the male reproductive part of the flower?

a) Calyx
b) Corolla
c) Androecium
d) Gynoecium

Solution: (c) Androecium is the male reproductive part of the flower

2) The unit of Calyx is known as ____

a) Ovule
b) Pollen
c) Sepals
d) Petals

Solution: (c) Sepals