Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Photosynthesis is the process by which green plants prepare their own food using sunlight, water (), and carbon dioxide ().
Leaves are known as the 'Food Factory' or 'Kitchen' of the plant because the process of photosynthesis takes place mainly in the leaves.
Chlorophyll is a green pigment present in the leaves that helps trap energy from sunlight. It gives leaves their green color.
Stomata are tiny pores located mostly on the underside of the leaf. They allow the plant to take in carbon dioxide () and release oxygen () and water vapor.
Plants take in water () and minerals from the soil through their roots, which are then transported to the leaves through the stem.
The food produced during photosynthesis is a simple sugar called glucose. Extra food is stored in the form of starch in different parts of the plant like roots, stems, leaves, or fruits.
Oxygen () is released as a byproduct during this process, which is essential for the survival of humans and animals.
📐Formulae
💡Examples
Problem 1:
Why is it important to keep a potted plant in the sunlight for it to grow healthily?
Solution:
Sunlight provides the energy required for photosynthesis.
Explanation:
Without sunlight, the chlorophyll in the leaves cannot trap the energy needed to convert water () and carbon dioxide () into glucose. Without food, the plant will eventually wilt and die.
Problem 2:
What happens to the glucose produced by a mango tree after photosynthesis?
Solution:
It is used for growth or stored as starch.
Explanation:
The tree uses some glucose for its daily activities and growth. The remaining glucose is converted into starch and stored in the mango fruit, which we eventually eat.
Problem 3:
During an experiment, a leaf is covered with a black strip of paper. Which part of the leaf will NOT show the presence of starch when tested with iodine?
Solution:
The part covered by the black strip.
Explanation:
The covered part did not receive sunlight, meaning it could not perform photosynthesis to produce glucose and store it as starch. When iodine is added, only the parts that performed photosynthesis will turn blue-black.