Page 21 - Science class 4

Unit-II : Flora World
Process of Food
3 Making in Plants

l Chlorophyll

l Structure of a leaf Sunlight Oxygen
Inside l How do leaves prepare food for a plant?
Inside
the l How do plants use the food made
the
Chapter Carbon
Chapter
by the plants? dioxide
l Relationship between plantsand animals Water Glucose
l Some unusual plants

Chlorophyll

Most plants that you see around are green in colour.
They appear green due to the presence of a

substance called chlorophyll in their leaves.
Chlorophyll helps the leaves to trap the sun's energy

and make food. Plants are often called 'our green
friends' because we depend on them for several

things like wood, food, oxygen, oil etc. Green leaves
of the plant are called the 'Food factories' or 'Kitchen'
of a plant. The process by which green leaves make

food in the presence of sunlight using chlorophyll,
carbon dioxide and water is called photosynthesis .

Quenching Scientific ThirstQuenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific Thirst
Quenching Scientific ThirstQuenching Scientific Thirst
Quenching Scientific Thirst
Extra water present in the plant is given out through the stomata. This
process is called transpiration.
Petiole Midrib STRUCTURE OF A LEAFSTRUCTURE OF A LEAFSTRUCTURE OF A LEAF
Leaf Blade
If we look at a leaf closely, we will see that it has a
flat part called the leaf blade . The tip of the leaf is

called leaf apex . A mid vein or midrib is seen

running through the middle of the leaf. There are
Vein
Small netted veins a number of side veins emerging from the midrib.
Structure of a Leaf
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