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Compare and contrast the adaptations of free-living flatworms and parasitic flatworms

The following image is of a diatom. it lives in water and gets food from photosynthesis. it is encased in a hard shell made of something similar to glass or sand . a diatom is a(n) because it has a) multi-celled organism; specialized parts. b) vertebrate; a skeleton. c) insect; an exoskeleton. d) single-called organism; only one cell.

Describe at least 2 abiotic and two biotic factors found in the desert biome how do these abiotic factors interact with the biotic factors