This chapter explains how plants perform essential life processes to grow, survive, and reproduce. It focuses on nutrition, photosynthesis, respiration, and transport of substances in plants. The chapter describes how green plants prepare their own food using sunlight, carbon dioxide, water, and chlorophyll. It also explains how plants respire day and night to release energy and how water, minerals, and food are transported within the plant body. The role of different plant parts such as roots, stems, and leaves is highlighted to show how plants function as living organisms.
Key Points
Plants are autotrophs, meaning they make their own food.
Photosynthesis is the process by which plants prepare food using sunlight.
Chlorophyll is the green pigment that traps sunlight for photosynthesis.
Carbon dioxide enters leaves through tiny pores called stomata.
Water and minerals are absorbed from the soil by roots.
The food prepared by plants is mainly glucose, which is stored as starch.
Oxygen is released as a by-product during photosynthesis.
Respiration in plants releases energy from food.
Plants respire all the time, both day and night.
Gaseous exchange in plants occurs through stomata and lenticels.
Xylem transports water and minerals from roots to other parts of the plant.
Phloem transports prepared food to all parts of the plant.
Transpiration is the loss of water as water vapour from leaves.
Transpiration helps in cooling the plant and upward movement of water.
Each life process is essential for the growth and survival of plants.
👉 👉Plants are living organisms that quietly support all life on Earth. By understanding their life processes, we learn to value plants and protect them, ensuring a healthy and balanced environment.