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.

The process shown in the picture, where carbon dioxide is taken in by the leaves and oxygen is released, is a continuous process that occurs in plants throughout the day.

Plants undergo photosynthesis, a process by which they convert carbon dioxide and water into glucose and oxygen, using sunlight as an energy source.

This process is essential for the plant's survival and occurs during daylight hours when sunlight is available.

Therefore, the correct answer is option D) All the time, as plants carry out photosynthesis during the daytime.

plants take carbon dioxide and give oxygen to humans

• Etiolation is a term used to describe the process that occurs when plants are grown in the absence of light or with greatly reduced light.
• When plants do not receive sufficient light, especially sunlight, they undergo certain changes to adapt to the low-light conditions. One of these changes is the yellowing of leaves.
• Leaves contain a pigment called chlorophyll, which is responsible for the green color and plays a vital role in photosynthesis, the process by which plants make their food.
• In the absence or reduction of light, the plant cannot produce sufficient energy through photosynthesis. As a result, chlorophyll breaks down, and the green color fades away. This leads to the yellowing of leaves.

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 have a remarkable ability to produce their own food through a process called photosynthesis. During photosynthesis, plants use sunlight, carbon dioxide from the air, and water from the soil to create glucose, which is a type of sugar. Glucose is the primary source of energy for plants.
• However, plants often produce more glucose than they immediately need for energy. To save this extra food for later use, plants convert the glucose into a different substance called starch. Starch is a complex carbohydrate that serves as a storage form of energy in plants.
• Similar to how we save extra food in a pantry or refrigerator for later consumption, plants store their extra food in the form of starch. The starch is stored in different parts of the plant, such as roots, stems, and leaves, and can be used when the plant needs energy but is unable to perform photosynthesis, such as during the night or in winter when there is less sunlight available.

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.

Plants are living organisms, and they share many characteristics with other living organisms. Let's go through each statement to understand why option C is the correct answer.

i. Plants are living organisms: This statement is true. Plants are living organisms because they have characteristics such as growth, reproduction, and response to stimuli.

ii. All organisms including plants are composed of cells, grow, reproduce, and respond to various kinds of stimuli like temperature: This statement is also true. All living organisms, including plants, are composed of cells, which are the basic building blocks of life. They grow in size, reproduce to create new individuals, and respond to stimuli from their environment, such as temperature changes.

iii. Sea anemone is a plant: This statement is false. Sea anemone is not a plant; it is an animal. Sea anemones belong to a group of animals called cnidarians and are related to jellyfish and corals.

iv. Plants have the ability to manufacture food, which distinguishes them from other living organisms: This statement is true. One of the unique characteristics of plants is their ability to perform photosynthesis, a process through which they manufacture their own food using sunlight, carbon dioxide, and water. This ability sets them apart from other living organisms that rely on consuming food from external sources.

Based on the explanations above, the correct answer is option C) i, ii, and iv, as statements i, ii, and iv are true, while statement iii is false.

Leaves are the structures of a plant that exchange gases. They have tiny openings called stomata on their surface, which allow for the exchange of gases such as carbon dioxide and oxygen.

A microscope is an instrument used to examine the cells of a leaf. A microscope is a scientific tool that helps us see objects that are too small to be seen with our naked eyes. It uses a combination of lenses and light to magnify tiny objects, allowing us to observe their details and structures.

In the context of examining the cells of a leaf, a microscope is particularly useful. It enables us to see the individual cells that make up the leaf and study their characteristics, such as their shape, arrangement, and any specialized structures they may have.

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.

Spines in cacti are actually modified stems. Cacti are a type of desert plant that have adapted to survive in arid environments with limited water availability. To reduce water loss and protect themselves from herbivores, cacti have evolved long, needle-like structures called spines.

Potatoes are a type of vegetable that grow underground, but they are not actually roots. Instead, they are a specialized part of the plant's stem called tubers.

Tubers are swollen, underground structures that store nutrients for the plant. In the case of potatoes, the tubers serve as a storage organ, storing starch and other nutrients that the plant needs for growth and survival.

While we might commonly refer to potatoes as "roots" because they grow underground, they are different from true roots. Roots are responsible for anchoring the plant in the soil, absorbing water and nutrients from the soil, and transporting those nutrients to other parts of the plant. On the other hand, tubers like potatoes store food and water reserves for the plant.

Asparagus is a type of vegetable where the part that we eat is the stem of the plant. Unlike many other vegetables where we eat the leaves, roots, or flowers, in asparagus, the stem is the edible part.