1. Chapter 2: Section 3 Chemistry of Cells
Most matter in your body that is NOT water is made of organic compounds.
4 Principle Classes of Organic Compounds:
Carbohydrates
Lipids
Proteins
Nucleic Acids

2. Carbohydrates Made up of Carbon, Hydrogen, and Oxygen atoms
Key source of energy
Found in foods such as Fruits, Vegetables, and Grains.

3. Sugars Disaccharides –2 or more sugars Monosaccharides
Polysaccharides – such as starch, are chains of 3 or more monosaccharides.
Monosaccharides
The building blocks of
carbohydrates.
Single sugars such as
glucose and fructose.

4. Lipids
Lipids are nonpolar molecules that are NOT soluble or mostly insoluble in water.
Include Fats, Phospholipids, Steroids, & Waxes
Important in the structure & function of cell membranes.

5. Lipids
Fats are lipids that store energy.

6. Protein/ Amino Acids Amino acids are the building blocks of proteins.
Some proteins are enzymes.
The protein, collagen, is found in skin, ligaments, tendons, and bones
Your hair and muscles contain proteins
Proteins called antibodies help your body defend against infection.

7. Foods as Fuels
Most foods contain a mixture of carbohydrates, proteins, and fats.
Your body’s cells harvest the energy in food molecules for metabolism.

8. Nucleic Acids All of your cells contain nucleic acids Two types: DNA
RNA

9. ATP
The ATP molecule stores energy when food molecules are broken down inside cells.
Cells need a steady supply of ATP to function.

10. Section 3 Energy is the ability to move or change matter.
Energy is in Food
Energy exists in many forms
Light
Heat
Chemical and mechanical energy
Electrical energy

11. Energy Chemical Reactions absorb or release energy.
Starting a chemical reactions requires activation energy.
Metabolism –describes all of the chemical reactions that occur within an organism.

12. Activation Energy
Activation energy is a “push” that starts a chemical reaction.

13. ENZYMES
Enzymes are substances that increase the speed of a chemical reaction.
Enzymes help organisms maintain homeostasis.
Without enzymes, chemical reactions would not occur quickly enough to sustain life.

14. Enzymes
Substrate – a substance on which an enzyme acts during a chemical reaction. Enzymes act ONLY on specific substrates.
An enzyme’s shape determines its activity.

15. Enzymes
Factors such as temperature and pH affect enzyme activity.

16. Energy and Chemical Reactions