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>> We have been talking about energy nutrients
and so what we have to talk about is how do we get energy?
Where does it come from?
There must be some connection to nutrients.
If you're playing basketball, you certainly need more energy.
There are a lot of words to know for this chapter: Metabolism,
catabolism, and anabolism.
Ultimately the beginning of energy photosynthesis
from the sun place of energy mitochondrion.
Energy in the body is adenosine triphosphate or ATP.
It's a lot of work to get ATP from an energy nutrient
so you got to think co-enzymes.
The steps involve glycolysis,
there is pierate [phonetic] lactate, acetyl-CoA, TCA cycle,
oxylow [phonetic] acetate, electron transport chain, GTP,
beta oxidation, deamination, and transamination.
All these words are keywords
in understanding the topic of metabolism.
Metabolism is the sum total of chemical reactions that occur
in the cell for it to be alive.
There are two types of metabolism.
There is anabolic and there is catabolic.
Anabolic reactions are ones that take something that is small
and build it into a larger unit.
So if you take a lot of glucose, not just two,
but if you take several hundred, you end up with glycogen.
Now, to build something up it takes -- it uses energy.
So an anabolic reaction uses energy
but if it's a carbohydrate, it will result in the building
of glycogen in the plant.
That's a building of starch.
If it is the lipid family, we've got glycerol and fatty acids
that will go through an anabolic reaction
and the result will be a triglyceride all cholesterol
or a phosphor lipid.
In the protein, we have to have the small molecules
of amino acids.
We undertake anabolic reactions,
and we will have the result of protein.
But in building that protein we use energy.
This chapter is not necessarily about anabolic reactions,
it's about catabolic reactions.
It's about taking a molecule.
It could be glucose.
It could be fatty acids.
It could be glycerol, or it could be amino acids
and breaking the bonds between the carbon and hydrogen
and releasing a potential energy and the result is the making
of adenosine triphosphate.
Try to remember how many carbons in glucose.
Do you remember?
It's 6. Carbons in fatty acids?
There's usually 18.
How many carbons in glycerol?
There's 3.
And what about amino acids?
Well, amino acids is a bit of a problem
because amino acids can have 2 or 4 or 6 amino acids
but it has nitrogen so you have
to deaminate an amino acid before you can release energy
and releasing energy would be those bonds
that hold the carbon to hydrogen.
Where does all this happen?
All this energy catabolism
or anabolism is all happening in the cell.
We know the cell contains a nucleus
because that contains the DNA
which is the code for making protein.
We know where protein is made.
It's made out there in the ribosomes.
Maybe we don't know much more than that about a cell.
If you haven't taken any more biology, you probably don't.
But there will be in a cell what is known as the powerhouse.
This is the place where energy is made for the use
of keeping the cell alive.
The powerhouse is really the mitochondria.
That's the plural.
The singular is the mitochondrion.
So this is where ATP will be made.
Probably when we think of metabolic organs --
the brain is metabolic, the muscles are metabolic,
but the liver, the liver is probably one
of the most active processing centers in the body.
So your book likes to say, "I love you with all of my liver."
Instead of with all of my heart
because if you really love someone,
your liver may be even more important than you heart.
So when think about what does the liver do?
It converts fructose and galactose to glucose.
It makes and stores glycogen.
It breaks down glycogen.
Certainly if glucagon comes to the liver,
it will breakdown glucose for energy.
It makes glucose from some amino acids.
It will convert excess glucose to fatty acids.
We know it -- the liver makes lipoproteins.
It can make triglycerides and phosphor lipids and cholesterol.
It can use fatty acids for energy.
It makes bile.
Proteins and the liver --
in the liver it will make nonessential amino acids.
It converts ammonia to urea.
It makes plasma proteins.
And in addition it detoxifies alcohol
and other drugs and poisons.
It dismantles all the red blood cells and takes the iron
out of those old red blood cells and recycles it.
The liver stores most of the fat soluble vitamins, A, D, E,
and K and many minerals.
Now, is that a list that says, boy eating liver is a good idea?
I'm sorry, but I just can't do it.
It's not food I enjoy.
I think I look too much on it detoxifies alcohol,
and it breaks down and builds fat so I don't really want it,
but some people really like it.
So what we have to understand is catabolism.