phytoplankton vs flora

phytoplankton and flora both are nouns.

Word	Noun	Adjective	Verb	Adverb
phytoplankton	Yes	No	No	No
flora	Yes	No	No	No

As nouns, flora is a hypernym of phytoplankton; that is, flora is a word with a broader meaning than phytoplankton:

phytoplankton: photosynthetic or plant constituent of plankton; mainly unicellular algae
flora: (botany) a living organism lacking the power of locomotion

Other hypernyms of phytoplankton include plant, plant life.

phytoplankton (noun)	flora (noun)
photosynthetic or plant constituent of plankton; mainly unicellular algae	(botany) a living organism lacking the power of locomotion
	all the plant life in a particular region or period