Olympiad Test: Plant Life -2 - Class 4 MCQ

• Cloves are often shaped like small nails or buds, which corresponds to the first line of the description.
• They are chocolate brown in color and have a distinctive strong smell, matching the second line.
• Cloves have analgesic properties and are commonly used to alleviate toothaches, as indicated in the third and fourth lines of the description. So, the correct option is (C).

The correct answer is b

The stem is the stalk or trunk of a plant. They pass the water and minerals onto xylem, which is a tissue that transports the water and minerals through the plant. We find xylem in both the roots and the stems of plants. This is also true of phloem, which is a tissue that transports food through the plant

The Reason Why Ananya's Sunflower Plant Died
Reason: The stem of the plant accidentally broke.
Explanation: The breaking of the stem caused a disruption in the plant's transportation system, leading to its eventual death. Here's a breakdown of the reasons why:
1. Lack of food transportation: When the stem broke, it severed the phloem tubes responsible for transporting food (sugar) produced by the leaves to the rest of the plant. This disrupted the plant's ability to distribute the necessary nutrients for growth and survival.
2. Water loss: The broken stem also caused a loss of water through the breakage. The stem contains xylem vessels that transport water from the roots to the leaves. With the break, water was unable to reach the upper parts of the plant, leading to dehydration.
3. Roots unable to supply water: As the stem broke, the plant's roots were still intact. However, without a functional transportation system, the roots were unable to supply water to the leaves. This further contributed to the dehydration and eventual death of the plant.
Conclusion: The accidental breaking of the stem disrupted the plant's ability to transport food and water, resulting in the death of Ananya's sunflower plant.

Plant found in Australia with very few leaves

• Characteristics: This plant has very few leaves and is commonly found in Australia.


• Usage: Local people tap into the trunk of this tree using a thin pipe to drink water.


• Identification: The plant described fits the description of an Oak tree.

Explanation:
The correct answer is B: 1, 3, and 4.
Reasons:
1. The mushroom feeds on decaying things while the rest do not:
- Mushroom is a decomposer and obtains its nutrients by breaking down dead organic matter. This is known as saprophytic nutrition.
- Coconut tree, cactus, and mimosa are autotrophs that can produce their own food through photosynthesis.
2. The mushroom is a fungus while the rest are not:
- Mushroom belongs to the kingdom Fungi, which is a distinct biological group separate from plants.
- Coconut tree, cactus, and mimosa are all plants belonging to the kingdom Plantae.
3. The mushroom cannot make its own food while the rest can:
- Mushroom lacks chlorophyll, a pigment necessary for photosynthesis, so it cannot make its own food.
- Coconut tree, cactus, and mimosa possess chlorophyll and are capable of photosynthesis to synthesize their own food.
Therefore, mushroom should be categorized differently from the other plants because it feeds on decaying matter, is a fungus, and cannot produce its own food through photosynthesis.

The correct option is Option C.

The given experiment demonstrates that oxygen is evolved during the process of photosynthesis. In this experiment, the aquatic plant-like Hydrilla is used. The aspect is the light reaction of photosynthesis. This is the process in which the plants with the help of chloroplast captures light energy. They can use the carbon dioxide from the air to produce carbohydrates in the form of sugar and starch. There is a splitting of water to fill the gap created by the electron in the photosystem. The product which is formed is oxygen which is liberated during this process.

Since, test tube B does not contain hydrilla in it, it will not form any gas.

Activity Description:
- Saumya covered a healthy leaf of a plant with black paper.
- The plant was left in the open for three days.
- Saumya then performed a starch test on both the covered and uncovered leaves.
Explanation:
- The process of photosynthesis, in which plants convert sunlight into energy, requires the presence of chlorophyll in the leaves.
- Chlorophyll is responsible for the green color of leaves.
- In the absence of sunlight, plants cannot perform photosynthesis, and the chlorophyll starts to break down.
- During this breakdown, the green color of the chlorophyll fades, and other pigments, such as anthocyanins, become more visible.
- Anthocyanins are responsible for colors like red, purple, and blue.
Outcome:
- When Saumya covered a healthy leaf with black paper, it was deprived of sunlight for three days.
- As a result, the chlorophyll in the covered leaf started to break down and fade.
- The fading of chlorophyll allowed other pigments, such as anthocyanins, to become more visible.
- The uncovered leaf, on the other hand, continued to receive sunlight and was able to maintain its chlorophyll content.
- Therefore, during the starch test, the uncovered leaf would turn blue, indicating the presence of starch, while the covered leaf would not show any change.
- Hence, the correct answer is option B: Uncovered leaves would turn blue.

Which part of a sugarcane plant contains food?
The stem of a sugarcane plant contains food.
Explanation: Here is a detailed explanation of why the stem of a sugarcane plant contains food:

• Sugarcane is a type of grass and the stem is the main part of the plant.
• The stem of the sugarcane plant is filled with sucrose, a type of sugar that serves as a source of food for the plant.
• The stem stores the food produced by the plant through photosynthesis in its tissues.
• The stem also transports water and nutrients from the roots to the leaves of the plant.
• When the sugarcane is harvested, the stem is crushed to extract the juice, which is then processed to produce sugar and other sugarcane-based products.

 

-Tape grass is an underwater plant that grows entirely submerged in water.
-Lotus is a fixed plant as its roots are anchored in the soil underwater, but its leaves and flowers float on the water’s surface.
-Pine trees commonly grow on mountains and in colder, elevated regions.
-Mould is a type of fungus, and it does not have chlorophyll, so it is classified as a non-green plant.