Chapter 8- Metabolism

This chapter is all about the changes that occur in a cell that enable it to "live". Metabolism really just refers to all the reactions (mostly chemical) in a cell that allow it to stay at homeostasis. The word metabolism comes from the greek word metabolē, or change. It's not just turning food into energy- its TONS of different complex chemical reactions working in sync with each other (to do things like maintain the cell structure, respond to it's environment, and synthesize energy for other functions). 

There are a lot of varying concepts presented in this chapter, pooled into a sort of metabolism blob. If that makes any sense....

So, here we go. 

First off, we have a bit of a chemistry lesson. If you've taken AP Chemistry, then you know all about Enthalpy, and Entropy. If those terms are gibberish to you, then you might want to check out these resources... (in fact, even if you are familiar with these terms, you should really watch the video. This guy is pretty great). 

So, now that we're clear on Entropy (and Enthalpy as well), we can move on to how this translates into biology. 

Side note:  Something I've discovered over this past year is that Chemistry and Biology are actually like a double helix- they revolve around each other. In an ideal world, they would be taught together, all mashed into one, but alas, we have our Chemistry classes, and we have Biology. 

The world of metabolism is highly controlled by ENZYMES. You might be wondering what the caps lock is for... well, it's that important. Remember back to some of my previous posts- an enzyme is a globular protein that has a specific shape and a specific chemical job. They are catalysts- which means they make reactions happen lightning fast. 

Now, this video is about Biological Molecules- so it's sort of review. But- it talks about proteins a bit, so I'm sticking it in this post. If you start watching, and feel like you already get it, well, then move on. 

Along with Enzymes comes a whole bunch of VOCAB. 

Here are some really important terms to know: 

Catabolic Pathways
Anabolic Pathways
Exergonic and Endergonic
Energy Coupling 
Phosphorylate
Substrate 
Substrate/Enzyme Complex
Allosteric Regulation
Feedback Inhibition
Cofactors
Cooperativity
Activation Energy
Competitive and Non-competative Inhibitors


Enzymes: 

And now for ATP- this is HUGE in understanding cell metabolism. ATP is pretty much the reason we function as human beings. (ok, so there's a bit more to it than that, but you know what I mean). 

Here's another great "Crash Course" Bio video on ATP. It goes a bit deep- so hang in there. 

And that's about all I have for you for today. Just remember- no amount of youtube videos can substitute a good textbook :) So make sure to be reading like crazy. 

Here's a comic, just for fun...