1. Energy and Metabolism

2. The Macromolecules Make up living organisms
Lipids (cell membrane, hormones)
Proteins (muscles, hair)
Carbohydrates (cell wall, exoskeleton)
Nucleic Acids (DNA, RNA)
But…where do we get the materials to make the biomolecules?

3. FOOD!

4. Metabolism = breaking + building
Food gets broken down (digested) into its basic units in order to gain energy and raw materials.
The raw materials are recycled to:
Build biomolecules and cells
The energy is used to do work:
Generate heat
Mobility and transport
Think

5. Metabolism = chemical reactions
Metabolism is the sum of all chemical reactions in the body.
A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.
Reactants  Products
CO2 + H2O  H2CO3

6. Chemical Reactions Require Energy
In order for a chemical reaction to occur, 2 conditions must be met:
Have enough energy for bonds to be made
Atoms are aligned just right that they can bond

7. Activation Energy & Enzymes
Often, the energy required for chemical reactions to occur is really high.
Takes a long time to carry out the necessary reactions…too long to sustain life.
How do living organisms overcome this?
ENZYMES (Proteins)
Biological Catalysts
Speeds up Rxns
Lowers energy

8. Enzyme Action Enzymes are not used up in the chemical reaction
The same enzyme can be used multiple times.
Enzymes are proteins that speed up chemical reactions
Requires less energy to complete each chemical reaction
Just like all proteins, their shape is highly specific.
Temperature and pH can have major effects on enzyme shape

9. Pineapple Enzyme - Bromelin
Used to ease pain and swelling.
Also, prevents gelatin from gelling.
How do you explain this observation?
Cup on left is not gelled.
Cup on right is gelled.
Both cups have pineapples in them, but one is canned and one is fresh.

10. Law of Conservation of Energy
Energy cannot be created nor destroyed, but it can be converted from one form to another
Some of that energy is lost as heat when converted.
The energy we can do work with is the usable energy
While enzymes reduce the loss of energy as heat, they are not 100% efficient.

11. Law of Conservation of Mass
Matter is neither created nor destroyed.
The same mass is present before and after the reaction.

12. Fin