The term that describes body structures in different organisms that have different outward appearances but develop from the same embryonic tissues is "homologous."
Explanation:
1. Homologous structures are similar structures found in different species that share a common ancestry and origin from the same structure in a common ancestor.
2. These structures may have different functions in various species, but they indicate evolutionary relationships and a common evolutionary history.
3. For example, the forelimbs of vertebrates like humans, bats, whales, and birds have different outward appearances and functions, but they all develop from a common embryonic structure known as the pentadactyl limb, indicating homology.
In contrast:
- Analogous structures perform similar functions in different organisms but do not share a common evolutionary origin.
- Remedial and vestigial structures have different meanings and do not relate to structures with different outward appearances but the same embryonic origin.
