Asingle-celled organism can be classified as a prokaryote based on the absence of —
a) a cell membrane b) ribosomes c) chromosomes d) a nucleus

As a bee feeds upon the nectar produced by a flower, the bee may become coated with the flower's pollen. as the bee flies from flower to flower, some of this pollen may contact a flower's pistil, resulting in pollination. this relationship between the bee and the flower is an example of a. parasitism b. commensalism c. mutualism d. competition