Life Processes in Plants - Class 7 Science Free MCQ Test with solutions

Stomata are tiny openings on leaves that let gases like carbon dioxide in and oxygen out. They also help control water loss.

• Plants have two main types of vascular tissue: xylem and phloem.
• Xylem transports water and minerals from the roots to the leaves.
• Phloem is responsible for transporting nutrients, particularly glucose produced during photosynthesis, from the leaves to non-green parts of the plant.
• This distribution ensures that all parts, including roots and fruits, receive the necessary energy to grow and function.

Roots take in water and minerals from the soil, which are needed for the plant's growth.

• Photosynthesis is the process by which plants convert sunlight into chemical energy.
• It occurs mainly in the leaves, using chlorophyll, the green pigment that captures sunlight.
• During this process, plants take in carbon dioxide from the air and water from the soil.
• Using sunlight, they transform these raw materials into glucose, a type of sugar, and release oxygen as a byproduct.
• This process is essential for the survival of plants and provides oxygen for other living organisms.

Xylem carries water and minerals from the roots to the rest of the plant.

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Why are other options incorrect?

a) Glucose

• Glucose is not a by-product.

• It is the main product of photosynthesis. Plants make glucose (a sugar) as food, which can later be stored as starch or used for energy.

b) Carbon dioxide

• Carbon dioxide is not produced in photosynthesis.

• Instead, plants take in CO₂ from the air as a raw material.

• Without CO₂, the process cannot happen.

d) Nitrogen

• Nitrogen is not involved in photosynthesis at all.

• Plants do need nitrogen, but they get it from the soil in the form of nitrates, not from the photosynthesis process.

Plants release carbon dioxide when they break down food to get energy, a process called respiration.

The word equation shows what plants need (carbon dioxide and water) and what they produce (glucose and oxygen).

Chlorophyll captures sunlight, which helps plants make food in the process called photosynthesis.

Starch is a type of sugar that plants store as energy, which they can use later.

Photosynthesis is the process by which plants make their food using sunlight, carbon dioxide, and water.

Plants take in carbon dioxide during photosynthesis to make food.

Transpiration pull is created when water evaporates from the leaves through stomata.
This evaporation lowers the water potential in leaf cells, pulling more water upward from the roots through the xylem.
It is the main driving force for the long-distance transport of water in tall plants.

Xylem carries water and minerals from the roots to other parts of the plant.

When iodine solution is added to a leaf containing starch, it reacts with the starch to form a blue-black complex, indicating the presence of starch in the leaf.