Yes, Organisms compete for the resources they need to survive like food, air, water, space. In areas where these are sufficient, organisms live in comfortable co-existence, and in areas where resources are abundant, the ecosystem boasts high species richness (diversity).
The endocrine system is a collection of glands that regulate your metabolism, growth, sleep, mood and other things around your body.
Photosynthesis - The cycle of plants and how they make energy! The sun(light energy), water, minerals and carbon dioxide are all absorbed by the plant. The plant then uses them to make glucose/sugar, which is the energy/food for the plant.
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