Photosynthesis puts oxygen in the atmosphere.
Protists are mostly unicellular organisms, whereas the fungi are mostly multicellular organisms. Molds are fungus-like giant structures. Protists can be either heterotrophs or autotrophs. Fungi contain a cell wall, which is made up of chitin.
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This is why it’s important to protect echo systems: Ecosystems are essential to our well-being and prosperity as they provide us with food, clean air and fresh water. Ecosystems also represent an exceptional source of outdoor recreation opportunities. The functions performed by ecosystems that increase our well-being are called ecosystem services.