tense up vs affect

tense up is not a noun while affect is a noun.

Word	Noun	Adjective	Verb	Adverb
tense up	No	No	Yes	No
affect	Yes	No	Yes	No

As verbs, affect is a hypernym of tense up; that is, affect is a word with a broader meaning than tense up:

tense up (noun)	affect (noun)
	the conscious subjective aspect of feeling or emotion

tense up (verb)	affect (verb)
cause to be tense and uneasy or nervous or anxious	act physically on; have an effect upon
become tense, nervous, or uneasy	have an effect upon
	make believe with the intent to deceive
	have an emotional or cognitive impact upon
	connect closely and often incriminatingly