Which level of organization is seen in both Arachnoidiscus ehrenbergii and the human stomach?

The correct answer is tissue.

Both Arachnoidiscus ehrenbergii (a type of diatom) and the human stomach are composed of tissues. Tissues are groups of cells that work together to perform specific functions. In Arachnoidiscus ehrenbergii, the tissue forms the structure of the algae, while in the human stomach, various tissues (such as epithelial, muscle, and connective tissue) work together to aid in digestion.

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