Page 106 - Science Class 06

THE FLOWERS 2. Calyx or Sepal : It is the outermost

Flowers are the main vegeta ve parts of the whorl of a flower which is green in
plant. They are found in different shapes, colour. It protects the growing flower or
sizes, colours and fragrances. The plants the buds. The whorl formed by sepal is
which bear fruits are called flowering called calyx.

plants. 3. Corolla or Petals : Petals form the
Structure of a Flower second whorl. These are coloured and

Flowers are the reproduc ve structures bright. They a ract insects for pollin-
produced by plants which belong to the a on. All the petals together form the
group known as angiosperms, or flowering whorl called corolla.

plants. This group includes an enormous 4. Androecium or Stamens : The stamens
variety of different plants ranging from are the male reproduc ve organs of a
bu ercups and orchids to oak trees and flower. Each stamen consists of a thin
grasses. There are about 250,000 known stalk or filament and a two lobed head
species. called the anther. Each lobe of the

Though flowers differ in shapes, sizes and anther contains a pair of sacs inside
colour, yet they have some basic parts. which pollen grains are produced. These
These parts are: pollen grains take part in reproduc on.

1. Pis l and Thalamus
5. Gynoecium or Pis l : The gynoecium
2. Calyx or Sepal consists of one or more female
3. Corolla or Petals reproduc ve organs called carpels. Each
4. Androecium or Stamen carpel consists of three parts— ovary

5. Gynoecium or Pis l (basal swollen part), style and s gma.
Petal Pis l is a s cky part which receive pollen
Stamen
Pis l grains. Style connects s gma with the
S gma
Anther ovary. The ovary bears the ovules on a
Style Filament raised ssue called the placenta. Each
Petal ovule cons tutes the female repro-
Ovule with
Ovary
Embryo Sac duc ve cell called ovum.
Sepel
Func ons of a Flower
Receptacle
Peduncle v Flower is the site of sexual reproduc on.
In this process, it produces fruits and
1. Pis l and Thalamus : The flower is born
seeds. The seeds germinate to new
on a stalk called pedicel. The p of the
plants.
pedicel is called thalamus or receptacle.
It is a condensed internode and bears v Flowers have different odour. So,
all the four whorls of a flower. different flowers are used to prepare
different types of perfumes.

106 Science-6