Depends upon the crash and/or landing. I've went down in a low speed low side in Olympia gel palm gloves with good knuckle protection and they tore at the seems (weren't made well, IMO). I slid/rolled/tumbled about 200 feet in MX gloves and they didn't even look like they even a part of the crash. It all comes down to how well they're made, just like anything else. I do not, however, suggest wearing MX gloves on a motorcycle. I do in the summer, but that's my choice. I have problems finding gloves that fit well, provide decent protection and still be able to feel the controls. But then...I have issues finding ANY gear that fits properly.
You asked earlier about mesh. If you're leaning toward mesh, especially during the summer, I suggest you look at how tight the weave is. Some mesh has a looser weave which could mean easier to rip apart if you do crash. The crash I had where I slid about 200 feet, I was wearing a mesh and it held up well enough for me to continue riding in it, although some people would probably chunk it and get another. Someone's opinion who I trust told me mine was good enough to continue riding it so I do. There's a reason alot of people call them one time slides...because they usually don't last but the one crash. A jacket should also fit snug. You don't want a loose fitting jacket that stands a chance of riding up during a slide. Road rash is a bitch.
I think most of us started out wearing some sort of boot that at least came to or a little over the ankle, then later moved on to a more motorcycle specific boot.
Pants: I'd love to find a pair of leather pants I can wear that fit properly with all the protection where it's supposed to be but it's impossible at my short stature. I'd prefer to wear leather or even some textile overpants...but that's not going to happen. So I wear jeans. However, I do suggest some overpants over if jeans, if nothing else. Or, if you can afford it eventually, maybe some draggin' jeans, although I've heard mixed reviews with them.
Helmet: Full face - where what fits well. Every brand and even their models seem to fit different according to head shape so be sure to try them on. They should also fit snug...almost tight...when they're new. The pads are extremely stiff when new and after a while of wearing the helmet will fit comfortably and still good. If it's too big, it can pop off your head if/when you go down. Look for the DOT and SNELL approved stickers on the back of the helmet.
Until you know your sizing in gear, it's recommended that you try on gear before purchase. In some places, it's cheaper to purchase gear online so if you go that route, make sure you check out their return policies. Some stores have excellent return policies, some have restocking fees, etc.
Other than that, welcome to the biking community, have fun, ride smart, and watch out for those damn cagers!
Keep the rubber side down.
