cartilage is a softer and more elastic than a bone and has a slippery surface in which it found where bone would rub together. in other words cartilage is somethings that helps your bones to to hit each other when they move.
Chondromalacia
It protects the articular cartliage.
it is a stout
catrilage covers the ends of bone and reduces the friction between them.
Rabbit ears are made of cartliage and blood vessels. The blood vessels help the rabbit keep cool in the summer.
It would mean the twelve year old has a cartilage piercing, nothing mystical about it, it's just a piercing.
Yes you can put retainers in just about any piercing, just be sure to do it after you have cleaned the piercings, it makes getting the retainers in a bit easier.
No more than 2-3 weeks. But, if you hit it or snag it of course it might get red but the constant discoloration shouldn't last long.
This is important so more oxygen is able to fill the space when breathing.
I believe cartilage makes up some parts of your bodies structures, such as your ears and nose, but it is also between joints, such as the knee joints to stop the constant friction from wearing the bone down.
Yes you can. I've had my cartilage pierced for 7 years and all I wear are regular earlobe studs. I even wear earlobe dangle earrings in my cartliage sometimes and its fine. No stretching or anything.
Cartilage never heals, at least not entirely, so the answer is subjective. The skin will close back up if the hole is small enough to begin with (22 Gauge is the basic earring post size), but the cartilage will retain it's fistula underneath.