6th Class Science Getting to know Plants / पौधों को जानना Plants

Plants

Synopsis

• A plant system is made up of different parts of a plant working together, each performing its own function.

• Based on size, we can divide the plants into herbs, shrubs and trees.

• All flowering plants have two main systems - the root system which grows underground and the shoot system which grows above the ground.

• Roots fix the plant firmly in the soil and absorb water and minerals from the soil.

• Root systems are of two types:
• Tap root system and
• Fibrous root system

• The shoot system consists of the main stem, leaves, buds, branches, flowers and fruits.

• The leaf is a green flattened structure, meant for manufacturing food for the plant body by the process of photosynthesis. A leaf consists of three parts, leaf base, petiole and lamina.

• If the veins and veinlets form a network, it is called reticulate venation. This is common in dicots. If veins and veinlets are parallel to the midrib, then it is called parallel venation. This is common in monocots.

• Flower is the reproductive part of the plant. The main parts of a flower are pedicel, thalamus, calyx, corolla, androecium and gynoecium.

• Androecium represents the male reproductive organs. It consists of stamens and anther lobes. Pollen grains, the male gametes are formed in the anther lobes. Gynoecium is the female reproductive organ. It consists of style, stigma and ovary. Ovary contains ovules. Female gamete (egg) is formed in the ovule.

• Roots get modified to store food, as in carrot, radish, sweet potato and dahlia.

• Stems get modified for storing food and water, providing support, growing new plants and manufacturing food.

• The process by which water comes out from the leaves in the form of water vapour is called transpiration.