The human body is mostly made up of oxygen, carbon, hydrogen, nitrogen, and other elements. It is also composed of around 65% water, 20% protein, 12% lipids, and smaller amounts of RNA, DNA, and other molecules. Proteins are an essential building block and worker molecule that serve seven main functions in the body: controlling chemical reactions as enzymes, muscle movement, transporting molecules, structure, acting as chemical messengers like hormones, providing immunity through antibodies, and being used as an energy source when in excess.

1. Introduction to the Human Body and Proteins

2. Think. Pair. Share. What are our bodies made-up of? - which elements? - what kinds of molecules? We are what we eat?

3. Introduction to the Human Body The average human is made-up of (by mass): - Oxygen (65%) - Carbon (18%) - Hydrogen (10%) - Nitrogen (3%) - Calcium (1.5%) - Phosphorus (1.0%) - Potassium (0.35%) - Sulfur (0.25%) - Sodium (0.15%) - Magnesium (0.05%) - Copper, Zinc, Selenium, Molybdenum, Fluorine, Chlorine, Iodine, Manganese, Cobalt, Iron (0.70%) - Lithium, Strontium, Aluminum, Silicon, Lead, Vanadium, Arsenic, Bromine (trace amounts) This person is not average.

4. Introduction to the Human Body In another sense: - Water (65%) - Protein (20%) - Lipids (12%) - RNA (1.0%) - DNA (0.1%)- - Other (1.9%) (you should know the order of these, don't worry about %'s)

5. Introduction to the Human Body

6. Introduction to the Human Body

7. Introduction to the Human Body

8. Introduction to the Human Body Proteins are the building blocks and worker molecules in our bodies. They have 7 functions:

9. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 1 – Controlling chemical reactions (proteins that do this are called enzymes ).

10. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 2 – Moving the body (muscles).

11. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 3 – Transporting molecules (like O 2 or lipids) around the body

12. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 4 – Structure (like hair, nails, muscles).

13. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 5 – As chemical messengers (hormones tell parts of the body to do things). Your brain can release hormones.

14. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 6 – Antibodies (which are proteins) help protect the body from disease. Pathogen Antibody

15. Functions of Proteins Proteins are the building blocks and worker molecules in our bodies. They have 7 functions: 7 – Excess protein can be used as a source of energy. Meat isn't the only food that is high in protein.