1. Unit 1E
Proteins

2. What are proteins?
Proteins are the “doers” of the cell. They are what gets stuff done.

3. What do Proteins do? What is their job?
Proteins help control cell function.
Proteins transport things throughout the body.
Proteins can tell organs how to function.
Proteins can speed up chemical reactions.
Proteins can form the “skeletal” support within cells…the cytoskeleton.
Etc…they are the “Doers”!!

4. What are the subunits of Proteins?
Amino Acids
There are 20 known amino acids on the earth.
The amino acids are put together in a certain sequence to form particular proteins.
The amino acids are joined together by Peptide Bonds.
The long chain of amino acids is called a polypeptide.
The polypeptide can then fold a certain way to make a protein. If the polypeptide folds a different way, it can create a different protein.
Folded Polypeptide
Polypeptide
Amino Acids
Peptide Bonds

5. What is important about the way proteins fold?
Depending on how the protein folds, it can have different functions.
The action of the protein can be turned on or off.
The protein can fold differently to have a completely different function.
When you heat a protein too much, it can unfold. This is called “denaturing”. If you denature a protein, it will not work anymore.

6. Why are proteins important to organisms?
Without proteins, nothing would get accomplished…
Food would not get digested.
There would be no hormones.
A stable internal environment would not be maintained.
Organisms can NOT live without functioning proteins. It is estimated that the human body has 10,000 different proteins that can be folded in over 100 different configurations…each…That is 1,000,000 different functioning proteins!!!

7. What organisms are proteins important to?
ALL Organisms

8. Examples of Proteins
The following are some VERY important examples of Proteins.

9. 1. Hemoglobin What type of organic molecule is hemoglobin?
Protein
What are the subunits of hemoglobin?
Amino Acids...just like all proteins.
What is the function of hemoglobin?
Hemoglobin is a protein on the surface of the red blood cells.
It carries oxygen from the lungs to the body via the red blood cells circulation through the body.

10. Hemoglobin continued
Describe the relationship between hemoglobin, red blood cells, oxygen, and the lungs?
The red blood cells travel to the lungs.
The hemoglobin on the red blood cells picks up the oxygen from the lungs.
The red blood cells flow through the body and drop off oxygen molecules where they are needed.
The red blood cells then travel back to the lungs to pick up more oxygen.

11. 2. Insulin What type of organic compound is insulin?
Protein
What are the subunits of insulin?
Amino Acids…just like all proteins
What is the function of insulin? What is its job?
Insulin is a hormone in animals used to control blood sugar levels.
Those whose insulin does not work are diabetics.

12. Insulin continued
Describe the relationship between insulin, blood, the pancreas, glucose, and glycogen.
When an animal eats sugar (glucose in particular), the glucose will move from the digestive track into the blood stream.
Once the glucose is in the blood stream, the pancreas will excrete the hormone, insulin.
Insulin packages the glucose together to create what?
Glycogen
The glycogen is then stored where?
The liver and muscles

13. Enzymes What type of organic molecule are enzymes?
Protein
What are the subunits of enzymes?
Amino Acids…just like all proteins
What are enzymes used for?
To catalyze (speed up) chemical reactions in the body.
What types of organisms use enzymes?
All organisms!! ALL chemical reactions within the body require enzymes…they would happen too slowly without the enzymes.

14. Enzymes continued
Describe the relationship between enzymes, folding, functionality, and specificity in enzymes.
Since enzymes are proteins, they can fold into different configurations.
Each different folding can change its function.
Different folding can also determine the enzymes specificity…
Specificity means, which reaction the enzyme is specific for…which reaction it will work for.
In short…the different way an way an enzyme folds will determine IF the enzyme will work and HOW it will work and WHAT it will work with.