2. HOW CELLS FUNCTION ALL CELLS NEED ENERGY AND MATERIALS FOR LIFE PROCESSES

3. CHEMICAL REACTIONS TAKE PLACE INSIDE CELLS ALL CELLS ARE MADE OF THE SAME ELEMENTS –All matter in the universe can be broken down into elements (about 100 different ones found on Earth) –25 are needed for life; 6 make up 99% of human body –Chemical Reactions make/brake bonds between atoms to make different molecules –ENERGY is needed to make bonds & is released when bonds are broken LARGE MOLECULES SUPPORT CELL FUNCTION (carbohydrates, lipids, proteins & nucleic acids) ABOUT 2/3 OF EVERY CELL IS WATER

4. CARBOHYDRATES Provides cell with ENERGY Simple carbs are SUGARS which are broken down in cell to release energy. Complex carbs are STARCH (sugars linked & stored together) and CELLULOSE (non- digestible in cell walls).

5. LIPIDS Are FATS, OILS, & WAXES, found in living things. Can store lots of ENERGY and used for structural support. Made of glycerol & fatty acids; doesn’t mix with water.

6. PROTEINS -Made of amino acids -Get amino acids from eggs, meat, beans & dairy -Used to build & repair; make enzymes for chemical reactions, help blood fight infections & carry oxygen

7. NUCLEIC ACIDS Are molecules that hold instructions for the maintenance, growth, & reproduction of a cell. 2 Types: DNA (holds information on how to make the body’s proteins) & RNA (copies data from DNA in nucleus and takes to cytoplasm so amino acids can link into protein) Made of nucleotides

8. ABOUT 2/3 OF EVERY CELL IS WATER All CHEMICAL REACTIONS inside a cell takes place in WATER. Water is made of H 2 O; 2 hydrogen atoms and one oxygen atom Water is found both inside & outside of a cell; the cell membrane’s lipid layer separates the 2 environments of water (inside & outside of the cell). The water hating tails in the lipids repel the water while the head clings to water.