1. Biology Unit 3

2. What is a Biomolecule?  Organic molecule made by living organisms  Consist mostly of carbon (C), hydrogen (H), and oxygen (O)

3. But wait…What is an Organic Molecule?  Organic Molecules: Contain carbon Considered the “chemicals of life”  Inorganic Molecules: Do not contain carbon

4. Monomers vs. Polymers  Monomers: Molecules that may react with similar molecules to form a chain  Polymers: A chain of many monomers that are chemically bonded together

5. Formation of Polymers  Animation Animation  How are polymers formed? Dehydration Synthesis (Condensation): Two hydrogen atoms and one oxygen atom are removed from the monomers to form water, and the two monomers are joined together.

6. Breakdown of Polymers  Animation Animation  How are polymers broken down? Hydrolysis—the reverse of dehydration synthesis (condensation) Water added to the polymer, un-linking the chain and breaking it back down to its original monomer units

7. Carbohydrates  What are they? Group of organic molecules that includes sugars, starches and cellulose.

8. Carbohydrates  Structure: Carbon, hydrogen and oxygen in a 1:2:1 ratio (CH 2 O) n – n is an integer such as 5 (C 5 H 10 O 5 ) Subunits: Monosaccharides, such as glucose or fructose Most often in a ring shape Subunits are connected with covalent bonds

9. Monosaccharide Example

10. Disaccharide Example

11. Polysaccharide Example

12. Carbohydrates  Function: Energy Structural Support Cell Wall Cell Membrane Marker

13. Lipids  What are they? Organic molecule group including fats and phospholipids

14. Lipids  Structure: Subunits: ○ Glycerol and fatty acids ○ Glycerol and fatty acids plus phosphate group Insoluble in water Do not form large polymers (2 or 3 fatty acids with glycerol) ○ Examples: diglyceride and triglyceride

15. Triglyceride Example

16. Phospholipid Example

17. Lipids  Function: Energy storage Insulation Part of cell membrane (phospholipids) Hormones

18. Proteins  What are proteins? Group of organic molecules that provides structure and facilitates chemical reactions.

19. Proteins  Structure: Subunits: Amino acids Amino acids connect via peptide bonds Very large molecules Globular or structural

20. Amino Acid

21. Proteins  Function: Lots of functions! Enzymes (speed rate of chemical reactions) Structural components in cells Mechanical functions in muscles and cytoskeleton (internal cell framework) Cell signaling Immune response

22. Nucleic Acids  What are Nucleic Acids? Group of organic molecules including DNA and RNA

23. Nucleic Acids  Structure: Subunits are nucleotides—5-Carbon sugar, Nitrogen base and one or more Phosphate groups

24. Nucleic Acids  Function: Storage and retrieval of information: ○ Encode genes ○ Gene expression