Olympiad Test: Living Organisms And Their Surroundings -2 - Class 6 MCQ

Chlorophyll is the green pigment found in the chloroplasts of plant cells, which is essential for photosynthesis, the process by which plants make food using sunlight, water, and carbon dioxide. Without chlorophyll, the plant cannot perform photosynthesis, even if it has other pigments like red. Therefore, Samantha is correct in stating that the plant cannot make food because it lacks chlorophyll due to its non-green leaves.

The two organisms in the pictures are likely a plant and a snail. Both organisms perform excretion, which is the process of removing waste products from the body. Plants excrete excess water and gases like oxygen, while snails excrete waste through their digestive system. Therefore, the common life process is excretion.

When plants grow in the dark, they lack sunlight, which is essential for photosynthesis. Without sunlight, the plant cannot produce the food it needs to grow properly. As a result, the plant becomes tall, weak, yellowish, and has small leaves, a condition called etiolation. This happens because the plant is unable to perform photosynthesis due to the lack of sunlight.

A response to stimulus refers to an action or change in behavior that occurs as a result of a stimulus.

• Option A: Watering of mouth when we see delicious food is a response to the sight (stimulus) of food.
• Option B: Closing of leaves of the mimosa plant when touched is a response to physical touch (stimulus).
• Option C: Shutting of eyes when an object is suddenly thrown is a response to the stimulus of the object’s movement.

However, Option D: A chick hatching out of an egg is not a direct response to a stimulus but is part of a natural developmental process. It does not occur as a reaction to an external stimulus. Therefore, it is not an example of a response to stimulus.

Features of the plant:

• Waxy upper surface of leaves
• Large and flat leaves
• Reduced size of roots
• Long and narrow stems

Explanation:
Based on the given features, we can determine the habitat of the plant:
1. Waxy upper surface of leaves: This feature helps in reducing water loss through transpiration. It is commonly found in plants that grow in dry environments.
2. Large and flat leaves: This characteristic is often observed in plants that need to maximize their surface area for photosynthesis. They are usually found in habitats with ample sunlight.
3. Reduced size of roots: Plants with reduced root size are adapted to habitats where water availability is limited. This adaptation helps them to conserve water effectively.
4. Long and narrow stems: Such stems are commonly found in plants growing in habitats with strong winds. The long and narrow shape helps them to resist wind damage.
Conclusion:
Considering the features mentioned, the plant described in the question is likely to belong to the desert habitat. Desert plants often have waxy leaves to reduce water loss, large flat leaves to maximize photosynthesis, reduced roots to conserve water, and long narrow stems to withstand wind.

A habitat is the natural environment where an organism lives, grows, and reproduces. It includes all the physical and biological factors that affect the organism.

• Option A: A desert with camels is a natural habitat for camels, adapted to the dry, arid conditions.
• Option B: A pond with fishes is a natural habitat for aquatic organisms like fishes.
• Option C: A jungle with wild animals is a natural habitat for various wildlife species.

However, Option D: Cultivated land with grazing cattle is a human-modified habitat, not a natural one. It has been altered for agricultural purposes and does not occur naturally like the other examples. Therefore, it cannot be called a true habitat.

Living organisms throw body wastes from their bodies through a process called excretion. Excretion involves the removal of metabolic waste products, such as urine, carbon dioxide, and sweat, from the body. This is essential for maintaining internal balance and health.

• Option A (respiration) is the process by which organisms take in oxygen and release carbon dioxide.
• Option C (digestion) is the breakdown of food into smaller components for absorption and energy.
• Option D (reproduction) refers to the process of producing offspring.

Therefore, the correct answer is excretion.

The control group in the experiment is the group that serves as a comparison to the test groups. It does not receive any sweetener in its food. The other three test groups consume different amounts of sweetener in their food.
Test groups:

• Group A: This test group receives 10 mg/day of sweetener in their food.
• Group B: This test group receives 50 mg/day of sweetener in their food.
• Group C: This test group does not receive any sweetener in their food.
• Group D: This test group receives extra food, but no sweetener.

Explanation:

• The purpose of having a control group is to provide a baseline for comparison. By not giving any sweetener to the control group, any changes observed in the test groups can be attributed to the sweetener and not other factors.
• Group A and Group B are the test groups that receive different amounts of sweetener in their food. These groups are used to study the effects of different dosages of sweetener.
• Group C is the control group that does not receive any sweetener. By comparing the results of Group C with the test groups, the researchers can determine the impact of the sweetener on various factors.
• Group D is not a test group related to the sweetener. It receives extra food, but no sweetener. This group may serve as a control group for other factors being studied in the experiment.

In conclusion, the control group in this experiment is the one that does not receive any sweetener in their food (Group C).

A streamlined and slippery body is a characteristic adaptation of animals living in water, such as fish or aquatic mammals. This body shape helps them move smoothly through water, reducing resistance and aiding in efficient movement.

• Option A (Water): This is the correct answer, as streamlined bodies are commonly found in aquatic animals.
• Option B: This is a duplicate of Option A, so it is also correct.
• Option C (Grassland) and Option D (Mountain): These environments typically do not have animals with streamlined bodies as a primary adaptation for movement.

Thus, the habitat of the animal is Water.