Question

The photoautotrophs require …………. to synthesize their own food.
(a) Carbon dioxide and water
(b) Chlorophyll
(c) Sunlight
(d) All of the above

Answer 1

Photosynthesis is a mechanism used to transform light energy into chemical energy by plants and other species that can later be released to fuel the activities of the organisms. In carbohydrate molecules such as sugars, which are synthesized from carbon dioxide and water, this chemical energy is retained, hence the photosynthesis term. Oxygen is often published as a waste product in most circumstances. Photosynthesis is done by most plants, most algae, and cyanobacteria; photoautotrophs are called such species.

Complete answer:
Autotrophic feeding is a mechanism in which in the presence of sunlight, an organism prepares its own food from basic inorganic substances such as water, mineral salts, and carbon dioxide. It is present in plants. Photosynthesis, which involves carbon dioxide, water, chlorophyll, and sunlight, is known as the mechanism by which food is prepared.
The significance of photosynthesis in the maintenance of life on Earth would be difficult to overestimate. There will soon be no food or other organic matter on Earth if photosynthesis stopped. The majority of life would die, and the Earth's atmosphere would become almost devoid of gaseous oxygen over time. Chemosynthetic bacteria, which are able to use the chemical energy of certain inorganic compounds and are therefore not dependent on the conversion of light energy, will be the only species able to survive under such conditions.

Additional information:
An autotrophic or primary producer is an organism that uses carbon from simple substances such as carbon dioxide to create complex organic compounds (such as carbohydrates, fats, and proteins), usually utilizing light energy (photosynthesis) or inorganic chemical reactions (chemosynthesis). They transform an abiotic energy source (e.g. light) into energy stored in organic compounds that other species (e.g. heterotrophs) can use. Autotrophs do not need a living source of carbon or electricity and are producers in the food chain, such as land-based plants or water-based algae (as opposed to heterotrophs as consumers of autotrophs or other heterotrophs). To make organic compounds for biosynthesis and as a stored chemical fuel, autotrophs can reduce carbon dioxide. Water is used as the reducing agent for most autotrophs, but others may use other hydrogen compounds, such as hydrogen sulfide.

So, the correct answer is ‘all of the above’.

Note:
-They are generally plant-origin species with some bacteria.
-Except for bacteria that appear to have a reddish hue, their color is greenish.
-They produce organisms.
-They take energy from the outside, use solar energy and geothermal energy in their process.