Grade 3 Science (NSO) : Flower, fruit and seed

Before starting lets take a look at the Grade 2 lessons

Plant – Types of plants

Plants – Parts we eat

Plants: Fruits

Plants : Uses of different plants

Flower

Responsible for reproduction

Colour and fragarence of flowers attract insects who act as pollinators.

Flower parts that we eat :

 

Pollination

Once the pollen meets the egg, a seed is formed.

Seeds are usually formed in a  fruit .

Once the fruit is mature, it releases the seeds. The seeds land on the soil and create new plants.

Seeds have many ways of moving. Sometimes the wind blows them about. When animals eat the berries, the seeds come out in their poop.

Some important terms :

  1. Nectar: sweet liquid in plants
  2. Pollen: powder or dust on flowers
  3. Anther: male part of flower, which produces pollen
  4. Pistil: female part of the flower, which moves pollen to the eggs
  5. Fruit: plant part that holds seeds

 

Fruits

Contains and protects the seeds

Plays an important role in the dispersal of seeds

Raspberries and blackberries are called aggregate fruit. They are made up of hundreds of little fruits. Each one contains a seed.

Structure of a fruit :

A fruit is divided into two layers . Pericarp and seeds.

Pericarp has 3 parts:

  • Epicarp, the outermost layer often consisting of only the epidermis
  • Mesocarp, or middle layer, which varies in thickness
  • Endocarp, the innermost layer of the pericarp which surrounds a seed in a fruit.

Seed

A small , round or oval object produced by a plant from which when planted a new plant can grow.

 

Fruits that we eat

Seeds

A seed is  the reproductive structure of a plant.  It possesses an embryonic plant covered in protective coat. Seeds come in differenent  shape, size and, color. The type of surface also varies from one seed to another. It may be smooth, wrinkled, striate, ribbed, pulpy or hairy.

Structure of a Seed:

A mature seed contains the plant embryo.

The seed has reserve food material for the growth of the plant and is  covered with a protective layer called seed coat.

Seeds are attached to the fruit wall by a small stalk known as the funiculus.

Radicle : This grows and develops into the root system of the plant.

Cotyledon : It is a significant part of the embryo within the seed of a plant. Upon germination, the cotyledon usually becomes the embryonic first leaves of a seedling.

Testa : The protective outer covering of a seed; the seed coat.

Micropyle : A small pore in the ripe seed which is useful in pollination.

Epicotyl : It is the shoot above the cotyledons and develops into leaves.

Seeds that we eat