placental vs placenta

placental and placenta both are nouns.

Word	Noun	Adjective	Verb	Adverb
placental	Yes	Yes	No	No
placenta	Yes	No	No	No

placental (noun)	placenta (noun)
mammals having a placenta; all mammals except monotremes and marsupials	the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus
	that part of the ovary of a flowering plant where the ovules form

placental (adjective)	placenta (adjective)
pertaining to or having or occurring by means of a placenta