The news comes just over an hour after the loan window had closed as manager Dean Keates and his backroom team continue to put in the hours in order to add to their somewhat understaffed squad.
Centre-back Johnson has joined on a season-long loan deal, while midfielder Ronan will remain with the club until January. Born in Kettering, 20-year-old Johnson joined Wolves in 2016 and gained experience on loan at AFC Telford United last season, scoring once in ten outings for the Bucks.
Ronan, also 20, has made 13 first-team appearances for the Molineux club and came off the bench in their 2-1 FA Cup fourth-round victory at Liverpool in January 2017. The Republic of Ireland Under-21 international spent the second half of last season on loan at Portsmouth, playing 16 times in League One.