Ecological efficiency is usually higher in aquatic ecosystems than on land,in part because photosynthetic protists do not make ____,as most land plants do.
A) chlorophyll
B) ATP
C) lignin
D) cellulose
E) organic material

Question

Ecological efficiency is usually higher in aquatic ecosystems than on land,in part because photosynthetic protists do not make ____,as most land plants do.  
A) chlorophyll
B) ATP
C) lignin
D) cellulose
E) organic material

Quizplus · Accepted Answer

Lignin is a complex organic compound present in the cell walls of many land plants that gives them structural support. However, lignin is not digestible by most organisms, and therefore it reduces the amount of energy that can be extracted from the plant material. Aquatic ecosystems, on the other hand, are dominated by photosynthetic protists like algae, which do not produce lignin, making the ecological efficiency higher.

Ecological Efficiency Is Usually Higher in Aquatic Ecosystems Than on Land,in