How do Plants Get Energy? | Definition and its Importance

Key Concepts

• Importance of food
• Food sources
• Requirements of plants to get energy: Air & Water
• Components of air
• Importance of water

Introduction

To stay alive, grow healthy, and perform various activities, all living things need energy, and we all know from our last session that living things get energy from food. 

Definition of food: 

Food is an edible substance eaten by humans and other animals to get the energy to do work, grow, maintain our bodies, and remain healthy. 

Importance of food 

• We know that all living things need food and water to live.  
• Food provides essential nutrients to help us grow and heal when we are injured or ill.  

• Thus, food keeps us healthy and provide us with essential nutrients to fight diseases and maintain body functions.  
• Different people eat various kinds of food according to their habits, lifestyle, taste, region, religion, availability, and various other factors. 

Sources of food 

Let us now learn about food variety and food sources. 

Plant source 

• For us, several parts of the plant serve as sources of food.  
• For example, we eat leafy vegetables, fruits, and some parts of plants like stems and roots. 
• So, we can say that green plants are the primary source of food. 
• Humans, some birds, and herbivores animals use plants as a source of food.  

Animal source 

Animal products used as food are: 

• Meat – Goat, chicken, pork, fish, prawns, etc.  
• Egg – Eggs of hen, duck, goose. 
• Milk – Dairy products obtained from cows, buffalos, camels, goats in a dairy farm. 
• Honey – Bees collect nectar (sweet juices) from flowers, convert it into honey and store it in their hive. 

• Humans, birds, and carnivores use animals as a source of food.  

Where do plants get their energy? 

Air and water 

Plants are living organisms. They also require food to get the energy to grow and to perform various activities in their body. From our previous session, we know that plants are producers. They can make their own food by using simple components. 

Three essential components required by the plants to get their food are: 

1. Air 

2. Water 

3. Sunlight 

1. Air 

Air is all around us. 

We can feel the presence of air but cannot see it around us. 

Air is a mixture of many gases. 

Carbon dioxide (CO₂)  

Carbon dioxide is one of the important gas in our atmosphere and around 0.4% in nature. We humans and animals, during respiration, produce carbon dioxide that is released into the air. 

Too much carbon dioxide is poisonous to our environment.   

2. Water (H₂O) 

Water is essential for all living organisms, around 71% of the earth surface is covered by water.  

Plants use water to make their food. Plants absorb water through their roots. 

3. Sunlight  

Plants get their energy from sunlight as they use sunlight during photosynthesis in the daytime. 

Summary:

1. We need food to get the energy to perform various activities.
2. Plants and animals are major sources of food.
3. Vegetables, fruits, grains, etc., are products of plants.
4. Milk, meat, cheese, etc, are products of animals.
5. Plants need sunlight, carbon dioxide, and water to make their food.