Though plants, fungi, and prokaryotes all have cell walls, we place them in different taxa. Which of these observations comes closest to explaining the basis for placing these organisms in different taxa, well before relevant data from molecular systematics became available?
A) Some closely resemble animals, which lack cell walls.
B) Their cell walls are composed of very different biochemicals.
C) Some have cell walls only for support.
D) Some have cell walls only for protection from herbivores.
E) Some have cell walls only to control osmotic balance.
The cells of eukaryotes (left) and prokaryotes (right)
Animal Cell
cell movement
Plant Cell
Interaction between a CD8+ T cell and its target.
Estimates of carbon stored in the plants and soils of different ecosystems.