Why are plants green in colour? - Chlorophyll & Photosynthesis - CBSE Class 4
Why are plants green in colour? – Chlorophyll & Photosynthesis – CBSE Class 4
You must have seen how your parents always want you to eat good and healthy food. The reason behind that is so you can grow to be healthy and strong.
Similarly, plants also require food to grow. In this blog, we will understand how they make their food and why are they green in colour.
Why are plants green in colour?
You must have seen how all trees and plants around you have leaves that are green in colour. That is because the leaves of a plant have a substance called pigment. This pigment is called Chlorophyll. This pigment is green in colour, so it makes the leaves of the plant appear green.
What part does chlorophyll play in photosynthesis?
Chlorophyll helps plants make their food. It assists plants to use carbon dioxide from the air, water from the roots, and energy from the sun.
Therefore, plants that do not have chlorophyll, and are not green, cannot make their food. For example – Mushrooms. Since mushrooms do not have chlorophyll, they are not green in colour. Because they do not have chlorophyll, they are unable to make their food.
How do plants make their food?
What is photosynthesis?
Plants make their food by a process called photosynthesis. Photo means light, and synthesis means putting together.
Therefore, chlorophyll helps plants use light to put together with other resources around them to make their food. The resources that they use are –
Water : When we water plants, the water gets absorbed by its roots through the soil. The roots help spread that water to the leaves through the stem. The leaves have faint lines on them called veins. They help transport water to different parts of the plant.
Carbon dioxide : When we breathe, we inhale oxygen from the air and exhale carbon dioxide. This carbon dioxide gets absorbed by the leaves of the plant using ‘stomata’. Stomata are the tiny pores below the surface of the leaves. These pores help the leaves to exchange gases and excrete excess water from the plant. These pores are so small that they are not visible to the naked human eye.
Sunlight : Chlorophyll in the leaves traps the energy of the sunlight. This energy enables plants to transform water and carbon dioxide into a kind of sugar called glucose. This glucose gets transported to other parts of the plants through the veins in the leaves.
Why is photosynthesis important?
The food we eat helps us grow tall and turn into healthy adults. Similarly, photosynthesis helps the plants to grow and make flowers, seeds and fruits.
Similar to the way we need to have healthy and nutritious food when we are sick to get fit, photosynthesis helps plants repair any damage they might have faced.
Starch : When plants form enough glucose, the process of photosynthesis continues. So the rest of the glucose gets converted to a substance called starch. It is a white solid carbohydrate substance that gets stored by all parts of the plant. That means the fruits, seeds, leaves, roots or stem store the starch.
Fun Fact #1 – The healthy food we eat is mostly plant-based. That includes the glucose and starch that plants produce by photosynthesis.
Fun Fact #2 – We can test the presence of starch in a plant by pouring an Iodine solution on the leaves. It turns the colour of the leaves from green to blue-black.
However, some plants do not depend solely on photosynthesis to make their food. Some plants also can eat small animals. Still, they have to perform photosynthesis to make most of their food.
Plants provide us with an excellent source of nutrition. If there were no plants, animals (herbivores) and humans would have almost no food to eat. It would ruin the ecosystem and put the entire food chain at risk. Therefore, we must preserve plants to the best of our abilities.
FAQs – Photosynthesis & Chlorophyll
1. What are stomata? Give the two functions of stomata.
Stomata are the tiny openings below the surface of the leaves of a plant. The two functions of stomata are –
A. exchange gases
B. excrete excess water from the plant
2. What is photosynthesis?
Photosynthesis is the process by which plants containing chlorophyll make their food. Photosynthesis puts together water, carbon dioxide, sunlight using chlorophyll to make up glucose and starch.
3. What is starch?
Starch is a white solid carbohydrate substance that is stored by all parts of the plant. That means the fruits, seeds, leaves, roots or stem store the starch.
4. What is chlorophyll?
Chlorophyll is a green colour pigment that gives leaves its green colour. Chlorophyll helps plants use light to put together with other resources around them to make their food.
5. What is the colour of leaves when we pour an iodine solution on them?
The colour of the leaves turns blue-black since they contain starch.
Here at Takshila Learning, we provide School Online Classes from Preschool to Class 12 for all subjects. We provide the best online tuition classes for Class 10 and other classes that comprise Animated Video lectures and Online Live Classes that will help students to grasp concepts easily. We also provide Worksheets & Assignments, Doubt sessions, Free Encyclopedia, NCERT Solutions for Class 10, and Exam Guru to monitor your progress, i.e., subject-wise and topic-wise. So now Enjoy E-Learning with Takshila Learning.
Tags: photosynthesis, what is photosynthesis, photosynthesis definition, photosynthesis process, photosynthesis meaning, chlorophyll, what is chlorophyll, chlorophyll structure, chlorophyll is present in, chlorophyll meaning, chlorophyll formula, the chlorophyll in photosynthesis is used for, chlorophyll definition, CBSE Class 3 photosynthesis, CBSE Class 4 photosynthesis