Well I go to a mid to lower tier university, and I know people at Russell Groups studying the same course (Biology). The main difference I see is that they have a lot more contact hours, and seem to learn a lot more content for modules that are similar, though I wouldn't say all of it is really necessary. My uni have minimal contact hours, and very few tutorials / seminars. Since September (I'm in second year), I've only had lectures and computer sessions, but no labs.
The uni I was at last year though (which was actually ranked even lower) had much higher contact hours, two tutorials a week, and one lab practical session every week. That was in first year, but I did get a chance to see the second year timetable before I left, and it was pretty much the same thing again.
So this just shows that the ranking of the uni doesn't always correlate with the contact hours, number of tutorials and lab sessions you'll have per week. I wouldn't really know why it's so different, but maybe it's to do with funding and the number of students on the course. There were a lot more Biosciences students at my uni last year, but at this uni (I transferred) it seems to be a pretty small group, so maybe that's why we don't have a lot of labs or tutorials.