yea, the ucr programs is a joint (now 8 year, used to be 7 years) bacc/md program (highly selective, people are kicked out as you go up each year in undergrad). here is some more info:
all three have separate apps and separate adcoms (well ucr is N/A for you bcz you would go to that from high school):
ucla-westwood: all 4 years at ucla, 121 spots.
ucla-drew: first 2 years at ucla, second 2 years at king/drew, 24 spots.
ucla-ucriv: 3 or 4 years of ucr for bacc, md: first 2 years at uc riverside, second 2 years at ucla. 24 spots.
hope that helps.