Answer:
Abiotic factors refer to non-living physical and chemical elements in the ecosystem. Abiotic resources are usually obtained from the lithosphere, atmosphere, and hydrosphere. Examples of abiotic factors are water, air, soil, sunlight, and minerals. Biotic factors are living or once-living organisms in the ecosystem.
Explanation:
Three important characteristics such as a notochord, a dorsal hollow nerve cord, and pharyngeal gill slits, should appear at any stage of their life cycle. These are the characteristics of the chordates. Members of echinoderms share resemblance with chordates in presence of a notochord.
The surface area to the volume ratio gets smaller as the cell gets larger. If the cell grows beyond a certain limit not enough material will be able to cross the membrane fast enough to accommodate the increased cellular volume.
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