I’ll second even sven’s suggestions that the entrance essay is the one chance you get to introduce yourself to the admissions staff and let them know who you are. You aren’t “candidate #1029381, GPA x.xx, SAT xxxx, Index score xxxx,” you’re Czaoth, a real person. At a party, you wouldn’t go up to someone you found interesting and introduce yourself by saying “Hi, I’m Czaoth, I’m xx ft. tall, xxx lbs, and I enjoy xxxxx and yyyyy.” So why do it on a college entrance essay?
Tell a story. Crack a joke. Be laid-back. Be yourself. Smile. Wait, scratch that last one; that’s for dates.
Show, don’t tell. If you want to convey that you’re a funny person, write an amusing story. Don’t write sob stories; if you write an “overcoming adversity” essay, put a positive spin on it. And definitely leave out statements that say, "so the whole point of this is to show that I’m…” It’s a college entrance essay, not an argumentative essay.
As for specifics, you say you want to talk about your internship at an animal research facility. When you talk about your internship with friends or family, what do you tell them? What do others ask you about the job? Put those things in your essay. Then, from that, pick out a couple things that you personally find most interesting and talk about that. Two pages aren’t a lot of room after all.
Above all, don’t feel that you have to impress your readers with your abilities, wow them with your knowledge, and amaze them with your strong moral character. Just show your readers that there’s a personality behind all the grades and test scores and you’ll do fine.
A copy of one of my favorite college entrance essays can be found here. It’s off-the-wall, but leaves me with the impression that I wouldn’t mind sitting down and chatting with the guy for an hour; the author seems interesting. And more importantly, he seems like a real person.
Best of luck to you, Czaoth.