Question

Which of the following statements about the autotrophs is incorrect?

• A. They synthesise carbohydrates from carbon dioxide and water in the presence of sunlight and chlorophyll.
• B. They store carbohydrates in the form of starch.
• C. They convert carbon dioxide and water into carbohydrates in the absence of sunlight
• D. They constitute the first trophic level in food chains.

Answer 1

The correct option is C

They convert carbon dioxide and water into carbohydrates in the absence of sunlight

The correct option is C.

The explanation for the correct option:

Option C:

1. A primary producer, also known as an autotroph, is an organism that uses energy from light or inorganic chemical reactions to create complex organic chemicals from simple ones, such as carbon dioxide.
2. It is false since autotrophs can only produce carbohydrates in the presence of sunshine when converting carbon dioxide and water.
3. Chlorophyll, a green pigment found in autotrophs, is able to capture solar energy.
4. Through the process of photosynthesis, they combine inorganic substances like CO₂ and H₂O to create food using trapped energy.
5. Food that is not consumed right away is stored as starch.
6. In food chains, these autotrophs make up the initial trophic level.

Explanations for the incorrect options:

Option A:

1. The majority of autotrophs produce their food through a process known as photosynthesis.
2. In photosynthesis, autotrophs use the sun's energy to turn carbon dioxide from the air and water from the soil into glucose, and nutrition.

Option B:

1. Chlorophyll, a green pigment found in autotrophs, is able to capture solar energy.
2. Through the process of photosynthesis, they combine inorganic substances like CO₂ and H₂O to create food using trapped energy.
3. Food that is not consumed right away is stored as starch.

Option D:

1. A food chain is a network of links in a food web that runs in a straight line from producer organisms to apex predators, detritivores, or decomposer species.
2. An organism that can make its own nourishment by the use of light, water, carbon dioxide, or other substances is an autotroph.
3. Autotrophs are also referred to as producers because they produce their own nourishment.
4. Every food chain's initial level is comprised of these.
5. Plants or single-celled creatures are the majority of autotrophs.
6. The majority of autotrophs produce their "food" (a nutrient called glucose) from sunlight, carbon dioxide, and water through a process known as photosynthesis.

Final answer: They convert carbon dioxide and water into carbohydrates in the absence of sunlight is the incorrect statement about autotrophs.