Reproduction through Seeds | Science Class 5 PDF Download

Plants that bear flowers are called flowering plants. Flower turns into fruits and fruits contain seeds. So we can say that flowers are the organs of reproduction for flowering plants. 

Parts of a Flower

A flower has the following four parts:

Each of these parts is arranged in a whorl (layer or round pattern) on the base of the flower.

Calyx

• It is the outermost whorl consisting of units called sepals.
• Sepals are green leaf-like structures at the base of a flower and enclose the rest of the flower in the bud stage.

Corolla

• Corolla is the next layer towards the top.
• Corolla is composed of units called petals.
• The petals are soft, brightly coloured, and the most beautiful parts of the flower.
• They attract insects, which help in pollination.

Androecium

• It is the male reproductive whorl consisting of units called stamens.
• The stamen is made up of filaments that have a swollen head at the top called the anther.
• The anther contains a yellow powder-like substance called the pollen grains.

Gynoecium

• Gynoecium is the innermost whorl of a flower, consisting of one or more units called the carpel.
• Carpel is the female part of a flower that consists of a long tube called the style.
• At the bottom of the style, a swollen base called ovary is present. Inside the ovary, ovules are present.
• The uppermost part of the style is called stigma.

Reproductive Parts of a Flower

• Sepals look like green leaves at the bottom of the flower. They protect the bud. 
• In most flowers, petals are brightly colored. They make the flowers look beautiful. They help to attract insects for pollination. 
• The stamen is the male part of the flower. It is made up of a thin stalk called the filament with a bag-like head called the anther. The anther contains the pollen grains. 
• The pistil is the female part of the flower. It consists of three parts:
  1. A swollen base called the ovary. The ovary contains small structures called ovules.
  2. A stalk arises from the ovary and is called the style.
  3. The style ends at the stigma at the top. 
• The flower is attached to a stalk called a pedicel. It is enlarged to form a receptacle found at the center of the base of the flower. 

Reproduction in Flowering Plants

Most flowering plants reproduce through seeds. This involves the following steps:

1. Adult plants produce flowers. 
2. Flowers have male and female parts. 
3. Male parts contain small grains of pollen.
4. The pollen grains of one flower are transferred to the female part of the same flower or another flower. This is called pollination. 
5. After pollination, the petals and stamens fall off. The ovary swells up and changes into a fruit and the ovules change into seeds. This process is called fertilisation. 
6. These seeds produce new plants. This is the life cycle of a plant.

Pollination

The transfer of pollen grains from the anther to the stigma of a flower is called pollination. 

• Birds and insects get attracted to colorful flowers. 
• Insects feed on the nectar from the flower, and the pollen grains from the anther stick to their bodies. 
• When the insects move to the stigma of a similar flower, the pollen grain falls on the stigma and pollination is carried out. 
• After some time, a tube known as the pollen tube comes out of a pollen grain and reaches the ovary through the style. 
• When the pollen tube reaches the ovary, fertilization takes place. 
• After fertilisation, the ovary of the flower grows into a fruit and the ovule develops into seeds.