1. Biochemistry Chapter 3

2. Water Section 2.3

3. Structure of Water  Held together by covalent bonds  2 atoms of H, 1 atom of O

4. Water is a Polar Molecule  Definition: a molecule with an uneven distribution of charge but a net charge of zero  Water bonds at an angle

5. Water’s ability to dissolve  “Like Dissolves Like”  Polar substances can dissolve polar substances, nonpolar substances can dissolve nonpolar substances

6. Questions:  Why don’t oil and water mix?  Why can water dissolve sugar or salt?  How does water dissolve a polar substance?

7. Answer:  The + end of water attracts to the – ion of the substance  The – end of water attracts to the + ion of the substance  This breaks the ionic bond of the substance thus dissolving it

8. Water’s special bond:  Hydrogen Bond: a weak chemical bond that exists between the H atoms and a – charged part of a different molecule

9. Water’s special properties: Due to H-bonds: 1. Water can cling to itself and other substances 2. Water is able to absorb large amounts of energy without changing temperatures quickly

10. Cohesion:  Definition: When like molecules are attracted to each other  Ex) surface tension in water

11. Adhesion:  Definition: the attractive forces between unlike substances

12. Capillarity:  Definition: cohesion and adhesion working together to move water molecules up a narrow tube against the force of gravity

13. Homeostasis? 1. The H-bonds in water are the first bonds to break when an increase in energy (temp) is applied 2. It takes a LARGE amount of energy to break/move water molecules 3. Thus, the temperature of water stays fairly constant in a cell even though there might be a drastic temperature change outside

14. Lab time….yeah!

15. Carbon Compounds SECTION 3.1

16. Organic Compounds  Organic compounds contain carbon atoms  Form covalent bonds with other C atoms or to other elements - N, H, and O.

17. Carbon Bonding  C readily covalently bonds (a bond forms when electrons are shared)  Each C forms 4 covalent bonds

18. Large Carbon Molecules  Polymers are made up of many small, repeating molecules called monomers.  Macromolecules- large polymers

19. Condensation Reaction  A chemical reaction that links monomers to form polymers  One water molecule is produced Ex) Glucose and Fructose combine to make Sucrose, table sugar

20. Hydrolysis  A chemical reaction that breaks down polymers  Reversal of condensation reaction  Usually done by adding water

21. ATP – Adenosine Triphosphate  All of life’s functions require energy  Energy compounds found in cells

22. Biochemistry The stuff life is made of! Section 3.3

23. The Four Molecules of Life  1. Carbohydrates  2. Proteins  3. Lipids  4. Nucleic Acids  All of your body is made up of these four types of molecules!

24. The Building Blocks  Each type of molecules is made up of smaller parts called monomers.  When 3 or more monomers are linked together, they form a polymer.

25. How to make a macromolecule.  How do you make a polymer from many monomers?  CONDENSATION REACTION!

26. Condensation Reaction:  The formation of larger molecules by removing a H + from one monomer and a OH - from the other monomer.  The H + and the OH - combine to form the bi-product H 2 O.

27. What will break up a large molecule?  The opposite reaction of condensation……  HYDROLYSIS REACTION! The use of water to break apart polymers back into monomers.

28.  Condensation/Hydrolysis Condensation/Hydrolysis

29. Monomers of the 4 Life Molecules  1. Carbohydrates - Monosaccharide  2. Proteins – Amino Acids  3. Lipids – Fatty Acids  4. Nucleic Acids - Nucleotides  How do you make macromolecules of each monomer? CONDENSATION REACTION

30. 1. Carbohydrates  Monosaccharide = monomer, simple sugar, ex) fructose, galactose, & glucose C 6 H 12 O 6  Disaccharide = 2 monomers, double sugar ex) sucrose (table sugar)

31. ________________________________________ Examples)

33.  Polysaccharide = 3+ monomers ex) starch & cellulose (in plants) glycogen (in animals)

34. 2. Protein  Amino Acid = monomer, 20 different types  Peptide bond holds amino acids together  Polypeptide = chains of amino acids

35. Most DIVERSE group of molecules Many structures such as muscles, skin, hair, and biological catalysts (enzymes) are made of proteins.

36. Enzymes  Protein molecules that catalyze (increase the rate of) biochemical reactions  How Do Enzymes Work? How Do Enzymes Work?  Animation: How Enzymes Work Animation: How Enzymes Work

37. 3. Lipids  Fatty Acids = monomer Hydrophilic Head - polar Hydrophobic Tail - nonpolar

38. Complex Lipids  Saturated Fats - bad  Unsaturated Fats - good  Phospholipids (cell membrane)  Waxes  Steroids

39. 4. Nucleic Acids  Nucleotide = monomer  Found in the genetic material DNA & RNA  carries out all of the functions of the cell