Enzyme analogy for honors bio? Can't use lock and key?

I can't use the lock and key because my teacher told us that one as an example so we could understand what she wanted so any help? I thought of a usb being plugged into a computer but i don't really like that one. I have also thought of plugging my iphone into the charger but i don't really think that is an analogy. Help Please! It is due tomorrow and it was just assigned today so no i haven't just been putting it off.

Thank you to all that answer.

Added (1). Thanks. I was just about to scrap the iphone idea but then i was looking at stuff for the iphone 5 and that has a different charger so i guess it would work now? Haha i hope so: P I think i will try that one and i'm sure i will hear other kids answers in my class so i will get lots of ideas. And i really like the puzzle piece one, that will be my back up.

Problem connecting iPhone to iTunes? - 1

Itunes could not connect to your iphone. An unknown error 0xe8000084 itunes
this comes up when i plug it in please tell me how to fix it
and also this comes up
iTunes has detected that it is not the default audio files. Would you like to go to control default panel to fix this. How do i fix these help me

Does iMessage for iPhone show up on the phone bill

I have an iphone 4. I'm wondering if iMessage shows up on the phone bill? If so, what shows up? I need to know if the times the messages were sent are on the bill, the number the iMessage was sent to is on the bill, or even if it's on the bill at all. I've heard that it isn't and that it is. It's very important please help! BTW I have unlimited talk and text but limited web.

HOW MUCH COULD I SELL MY IPHONE?

I have a 32gb white iPhone 4, not scratches or anything works great still have the box and everything (charger.etc) and 2 almost new otter boxes, how much could I sell then for?

Do I need to unjailbreak my iPhone 4s before updating iOS 6?

I have my iPhone 4 S jail broken, I have cydia & I purchased tetherme for $5. I don't want to lose my subscription to tetherme but I do want iOS 6. Do I need to un jail break it before updating the iOS? Once they come out with the iOS jail break will I have access to Tetherme through Cydia still?

I really don't want to brick my phone - so most importantly, do I need to do anything before upgrading to iOS 6?

Does all Iphone 4S units have drop call issues?

I'm looking at upgrading my BB phone to an Iphone 4S. The 4S is now selling for $99 + activation at ATT. Before I head out I do know the major drawbacks from this model since it was first released. I'm not a big Iphone upgrade fan and definitely not going for the Iphone 5 as well. There's not much difference at all for me from both models and no need for anyone to convince me otherwise. Now If all units have this problem I'd rather go with another BB upgrade instead.

What happens if I upgrade to IOS 6 and my iPhone is jailbroken?

Hi I'm running on IOS 5.1.1 and my phone is jailbroken. I want to upgrade to IOS 6 but I don't want to unjailbreak my phone. I would do the download from my phone an not a computer. So would cydia and installaous and all that be deleted or just not able to boot up? Thanks ps I have siri which I got from cydia and I wanna know if that will be gone? Or just not work?

Mac not allowing me to update to OS X 10.6.8?

I'm currently running my Mac on OS X 10.5.8 (snow leopard).

This all started when I tried to update my iPhone to ios 6.

In order to do that, I need to update my iTunes to iTunes 10.7.

Downloaded that, Mac told me I need Mac OS X version 10.6.8 or later.

Downloaded that, Mac told me the update requires Mac OS X version 10.6.

I can't find version 10.6 for download on the internet. System updates is not showing any updates available.

Please help me figure out how to resolve this problem.

My iphone will not connect to itunes after upgrading to ios 6?

I just upgraded my iphone 3gs to ios 6 not sure if it updated but now when i turn on my phone it says automatically that i need to connect it to itunes using the USB port but when i connect it it comes up as new hardware and can't find a program/software for my device even though i have the latest itunes on my computer. I have tried reinstalling itunes but it still can't find my phone and now i can't use my phone as it is stuck on the sync to itunes screen