Role of Infantry:
To run around in the snow and mud, bitching constantly how the training sucks only to retire to your mess and brag how hard you are.
Role of Medics:
To sit around on the range drinking coffee waiting for something bad to happen. (female) To be leered at in the meal line by a hundred horny guys on course.
Role of MPs:
To have a pickle up your ass and pull over cars doing 40 on base because he was driving without a hat.
Armoured Recce:
To ensure that all en has fled an area by using vehicles that are outdated and really really loud. "We're in the ORV, time to pull out your drip-pans."
Sup Tech:
To ensure all soldiers know that it's easier to hold a piece of kit than a piece of paper.
Wep Tech:
To fix all the busted weapons that Meaford sends to Pet every year.
Okay, now that I've offended just about everyone here, I'll help you out.
The role of the armoured reconnaissance squadron is to collect accurate tactical information about the enemy and the ground in all phases of war and to pass this information quickly to formation HQ. -source queens york rangers website
For the MPs, I couldn't find anything specific. Here's a link to the 25 MP site.
http://www.geocities.com/Pentagon/2931/platoon.html
Here's a page for Sup Techs
http://www.forces.gc.ca/admmat/logbranch/handbook/Volume7/chap1_e.htm