Welcome to Bodhiclasses – your learning companion dedicated to making science fun, clear, and deeply understandable. Today, we explore an essential chapter in the Class 7 Science curriculum: Life Processes in Plants. This chapter dives into how plants grow, make food, transport nutrients, and even breathe – yes, plants do respire!
🌱 How Do Plants Grow?
Plants don’t eat like animals, but they surely need food, water, and sunlight to grow. An engaging experiment in the chapter shows that:
- Plants given sunlight and water thrive the most.
- Those without sunlight or water show poor growth or die.
This proves that both sunlight and water are vital for a plant’s healthy development.
🍃 Leaves – The Food Factories of Plants
Unlike animals, plants make their own food in a process called photosynthesis. The broad, flat green leaves are the main sites where food is prepared. The green pigment chlorophyll helps trap sunlight, which is necessary to convert carbon dioxide and water into glucose (a type of sugar) and oxygen.
Word Equation for Photosynthesis:
Carbon dioxide + Water → (in presence of sunlight & chlorophyll) → Glucose + Oxygen
Experiments using iodine reveal that starch (stored glucose) forms only in green parts of leaves exposed to sunlight.
🌬️ Air and Gas Exchange in Plants
Plants absorb carbon dioxide from the air and release oxygen during photosynthesis. This exchange of gases happens through tiny pores on leaves called stomata, which can be observed under a microscope.
Another experiment using caustic soda shows that when carbon dioxide is removed from the air, starch is not formed—proving carbon dioxide is essential for photosynthesisgecu110.
💧 Transport of Water and Food in Plants
- Xylem – Thin tube-like structures that carry water and minerals from the roots to the leaves.
- Phloem – Transports the prepared food from leaves to other parts of the plant.
An experiment using red ink visually demonstrates how water travels through xylem into leaves and flowersgecu110.
🌿 Do Plants Respire?
Yes! Just like animals, plants respire. They break down glucose in the presence of oxygen to release carbon dioxide, water, and energy. This energy supports growth and other life functions.
Word Equation for Respiration:
Glucose + Oxygen → Carbon dioxide + Water + Energy
A clever experiment using lime water and germinating seeds shows carbon dioxide production, confirming that plants breathe too.
🧪 Summary of Key Concepts: Life Processes in Plants
- Photosynthesis is the process by which plants make food using sunlight, water, carbon dioxide, and chlorophyll.
- Leaves are the main site of food production.
- Stomata allow exchange of gases (CO₂ in, O₂ out).
- Xylem transports water and minerals; Phloem transports food.
- Respiration in plants releases the energy they need to grow.
🧠 Why Life Processes in Plants is Important?
Understanding the life processes of plants – how plants sustain themselves reveals how vital they are for the environment. They:
- Create oxygen,
- Form the base of food chains,
- Play a crucial role in maintaining the balance of gases in our atmosphere.
💡 Did You Know?
- Ancient Indian texts like Vrikshayurveda discussed plant growth techniques and organic manure preparation centuries ago.
- Scientist Kamala Sohonie made groundbreaking contributions in plant respiration and nutrition research.
