1 Key Questions: What are the major chemicals in living things?

2 1. Characteristics of Proteins Proteins are organic molecules. They contain carbon, hydrogen, oxygen and nitrogen, and sometimes sulfur.

3 2. Examples of Proteins What parts of people are mostly made of protein? 1. ________________ 2. ________________ 3. ________________

4 1.Muscle 2.Hair 3.Nails

5 Did you eat any protein for breakfast?

6 Food Sources of Protein Meat: Beef, Pork, Poultry, Seafood Dairy products (milk cheese, yogurt, cottage cheese) Beans Nuts Soy beans and tofu

7 Why do we need protein in our diets? Our bodies cannot make all the amino acids needed. We need to get 8 amino acids from our diet We call these the 8 essential amino acids

8 essential amino acids Isoleucine Leucine Lysine Methionine Phenylalanine Threonine Tryptophan Valine Muscles Blood, Muscles, Hormones Herpes, triglycerides Hair, skin Depression Collagen, tooth enamel Depression muscles 8

9 Plant material does not contain the 8 essential amino acids People who are vegetarians must eat a combination of beans and rice to obtain all the essential amino acids

10 3. Uses of Proteins Structural- They serve as the building and binding materials of living things.

11 Most cell structures are made from proteins

12 Growth and Repair

13 Transporting material Ex. Hemoglobin transports oxygen in blood cells

14 Movement Ex. Collagen is a protein that forms tendons, ligaments, and cartilage

15 Enzymes Control rate of reaction and regulate cell processes Ex. Insulin lowers blood sugar

16 A catalyst that lowers the amount of energy needed for a reaction to occur. Almost every cellular reaction has an enzyme

What happens if you don’t have a certain enzyme? If you are lacking an enzyme, you aren’t able to break down certain proteins. For example, if you are lactose intolerant, you are missing the enzyme lactase. 17

18 4. Structure of Proteins Building blocks are amino acids. There are over 20 different amino acids. Cells combine amino acids in different ways to form thousands of different proteins.

19 Macromolecules –Proteins Amino acids form chains that can fold and spiral and make complex protein structures.

20 General Design

21 5. Unique Property of Proteins How are the amino acids in proteins like letters in a word?

22 How many letters in the alphabet? ____ Letters make _____ Words can be big or little. Unlimited # of words.

23 How many amino acids? ____ Amino acids make _______ Proteins can be big or little. Unlimited # of _________

24 Making Connections On the side of a Diet Coke can it says WARNING: Contains Phenylalanine. Why would a person need to worry about an increase of an essential amino acid in their diet?