A theory by which prokaryotes gave rise to the first eukaryotic cells. Chloroplasts in plants and mitochondrion in other eukaryotes are believed to have once been prokaryotic organisms engulfed by larger prokaryotic cells.

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

easy

explanation: