A
plant-animal relationships
B
plant-plant relationships
C
animal-animal relationships
D
protozoan-sponge relationships
Solution:
The most spectacular and evolutionarily fascinating examples of mutualism are found in plant-animal relationships. In the case of plant-animal relationships, plants need animals to help them with pollination and seed dispersal, while animals need plants as a source of food and shelter. In exchange for their help, these pollinators receive a reward in the form of nectar or pollen from the plant. The nectar provides the pollinators with energy, while the pollen can be used as a food source or to build nests. Seed dispersing animals receive a reward in the form of juicy and nutritious fruits from the plant. The fruits provide the animals with a source of energy and nutrition, while the seeds are dispersed throughout the animal’s habitat.