BrainBashers – Puzzle ZZTF – ?

Here is a set of five clues for five words that only differ by one vowel (vowels are AEIOU, but not necessarily in that order). What are the words?
Small robot.
Small part.
On the contrary.
Nocturnal mammal.
Wager.

Here's another set of clues for five new words:
Struck.
Heated (archaic British).
Straw dwelling.
A head warmer.
Not cold.

Puzzle Copyright © Kevin Stone

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