Olympiad Test: Plant Life -1 - Class 4 MCQ

Plants are autotrophs, which means they produce their own food. They use the process of photosynthesis to transform water, sunlight, and carbon dioxide into oxygen, and simple sugars that the plant uses as fuel.

Transpiration is the process by which plants lose water through their leaves. It is similar to how we sweat to cool down our bodies. During transpiration, water evaporates from tiny pores called stomata on the surface of the leaves. This helps plants to transport water and nutrients from the roots to the rest of the plant.

Therefore, the correct answer is option (C) Transpiration.

• Stomata are tiny openings or pores found on the surface of leaves. They play an important role in the process of photosynthesis, which is how plants make their food.
• Stomata allow gases to enter and exit the leaf. One of their main functions is to take in carbon dioxide (CO₂) from the air. Carbon dioxide is an essential raw material for photosynthesis.
• Inside the leaf, with the help of sunlight and chlorophyll, carbon dioxide combines with water to produce glucose (sugar) and release oxygen as a byproduct.

So, the correct answer is option (A) Carbon dioxide for photosynthesis.

Mushrooms are unique organisms that belong to a group of organisms called fungi. Unlike plants, mushrooms do not have the ability to produce their own food through photosynthesis.

Instead, they obtain their nutrients by breaking down and feeding on dead and decaying plants, trees, or other organic matter. This process is known as decomposition.

Plants store extra food in the form of starch, which is a complex carbohydrate. Starch is made from glucose (a simple sugar) produced during photosynthesis. The starch is stored mainly in the roots, stems, and leaves of the plant and can be converted back into glucose when the plant needs energy.

• In a carrot plant, the food is stored in the roots. The carrot is a root vegetable, and the orange part that we eat is actually an enlarged taproot of the plant. Taproots are thick and fleshy roots that have the capacity to store food for the plant.
• During the growth of a carrot plant, the leaves of the plant use sunlight to produce food through the process of photosynthesis.
• This food is then transported and stored in the roots in the form of carbohydrates, such as sugars and starches. The roots of the carrot plant act as a storage organ, saving the extra food produced by the plant.

Plants need water for their survival and growth. To get water from the surroundings, plants have specialized structures called roots. Roots are usually found underground and are responsible for absorbing water and nutrients from the soil.

An example of a fruit containing seeds that is edible to humans is a tomato. Although we often think of tomatoes as vegetables, botanically they are classified as fruits. The tomato plant produces fruits that are typically red, round, and juicy.

The main purpose of flowers is to provide seeds. Flowers are the reproductive structures of plants. They produce seeds, which are essential for the continuation and propagation of plant species.

• Leaves play a crucial role in the process of photosynthesis, which is how plants make their own food. One of the essential requirements for photosynthesis is sunlight. Leaves are specially designed to capture sunlight effectively.
• Leaves have a large surface area, which means they have a lot of space exposed to sunlight. This large surface area allows leaves to absorb as much sunlight as possible. Sunlight contains a type of energy called solar energy, and leaves absorb this energy to initiate the process of photosynthesis.
• During photosynthesis, leaves also absorb carbon dioxide from the air through tiny pores called stomata. However, the main purpose of leaves is to capture sunlight rather than carbon dioxide.

Pine trees, along with deodar, cedar, and fir, are found in the hills. These trees have needle-shaped leaves and a conical shape, which helps in preventing snow from getting deposited on them. They are tall, straight, and evergreen, making the hills appear green and beautiful.

The leaves of a plant are the main structures responsible for gas exchange. Through small openings called stomata, leaves take in carbon dioxide (CO₂) from the air for photosynthesis and release oxygen (O₂) as a byproduct. This process is called respiration and photosynthesis.

Lotus and water lily are examples of fixed aquatic plants. These plants are attached to the bed of the water body and have broad leaves. In contrast, water hyacinth, duckweed, and water lettuce are free-floating aquatic plants that float on water without being attached to the surface.

A microscope is an instrument used to examine very small objects, such as the cells of a leaf, which are not visible to the naked eye. The microscope allows us to magnify the cells and study their structure, such as the cell wall, chloroplasts, and other organelles. Other instruments like telescopes, magnifying glasses, and cameras are not designed to magnify objects at the cellular level. Therefore, the correct instrument for examining leaf cells is a microscope.

• Stomata are the tiny pores or openings found on the surface of plant leaves (and some other plant parts). They are like small mouths or windows that allow for the exchange of gases and water vapor between the plant and its surroundings.
• Stomata play an essential role in the life of a plant. They allow carbon dioxide, which is needed for photosynthesis, to enter the leaf. At the same time, they release oxygen, which is produced as a byproduct of photosynthesis, and excess water vapor through the process of transpiration.