Autotrophic activityin plant cells occur in organelles called ...

An ecosystem consists of the whole community of living organisms (biocenosis), the abioticcomponent of a certain environment (biotope) and their relationships.
The relationships essentially consist in a flux of substances which pass from thenon-living components to living ones and in a flux of energy which passes from thephotosynthetic organisms (plants) to the herbivorous animals, then to carnivores. Thewastes and the dead organisms are then decomposed by the micro-organisms which brake downthe substances back to simple components, in a full cycle.
1 - With a shovel in a field or in a wood, dig a square hole of about half a meter (1 1/2feet) square and about 40 cm (18") deep. Describe the non-living components of thesoil and all forms of life you find: roots, earthworms, snails, centipedes, spiders,crickets, etc. To complete the description of the ecosystem of the soil, look forinformation on the role of each of these organisms and the relationships with the otherforms of life of this environment.
2 - In similar way you have studied the soil ecosystem, you can analyze other ecosystemssuch as the ones in a forest, pond, shore, or desert.
G. and L. Durrell (2) can be useful, or there are many other books on this matter.
An Illustration of a Soil Ecosystem
Protocols for a Soil Ecosystem Approach for Characterizing Soil Biodiversity
Internet keywords: soil ecosystem.

The raw materials used in photosynthesis are carbon dioxide and water.

Plants absorb water through their roots, and carbon dioxide through their leaves. Some glucose is used for respiration, while some is converted into insoluble for storage. The stored starch can later be turned back into glucose and used in respiration. Oxygen is released as a by-product of photosynthesis.

The raw materials for photosynthesis are carbon dioxide and water

our topic right now, namely photosynthesis,is arguably one of the most important chemical reactions occurring on theplanet. Let's see why.