3. Organic Molecules Carbon = building block of organic molecules Carbon is unique – 2 nd electron level not full – Only has 4 electrons in 2 nd level – Will bond up to four times Monomer: Small carbon molecules – Ex: Amino acid Polymer: chain of linked monomers – Ex: Protein Amino acid Polymer (protein)

4. Is Carbon stable with 4 electrons in its outer layer? Is Hydrogen stable with 1 electron in its layer? So what do atoms do when they are unstable? Problem: Drawing dot diagrams is time consuming. Try this instead!

5. Carbon creates 4 bonds to be stable

6. Carbohydrates Readily available food source C 1 : H 2 : O 1 ratio C 1 : H 2 : O 1 ratio – Ex: Glucose = C 6 H 12 O 6 Monomer: Monosaccharides – Simple sugars – Bond to form larger sugars Polymer: Polysaccharide – Complex sugars Glucose (monosaccharide) Fructose (monosaccharide) Sucrose (Polysaccharide)

7. Carbohydrate Polymers: Polysaccharide Long chain of monosaccharides Ex: Starch (pictured) : excess plant sugar converted & stored Ex: Glycogen: starch animals store in liver & muscles Ex: Cellulose: starch stored by plants to make cell walls

8. REview 1)How many electrons does Carbon have in the 1 st energy level? 2 nd energy level? 2)Which type of organic molecule is most commonly used as energy for cells? 3)If a carbohydrate has 8 carbon atoms, how many oxygen and hydrogen atoms will it most likely contain? 4)What are the monomers of carbohydrates called? 5)What are the polymers of carbohydrates called? 6)Which polymer of carbohydrates is stored by animals? 7)Which polymer of carbohydrates is stored by plants?