1. Chapter 2 THE CHEMISTRY OF LIFE

2. California State Standards  1h: most macromolecules in cells and organisms are synthesized from a small collection of simple precursor  4e: proteins can differ from one another in the number and sequence of amino acids  1b: enzymes are proteins that catalyze biochemical reactions without altering the reactions equilibrium and the activities of enzymes depend on the temperature, ionic conditions, and the pH of the surroundings

3. CHAPTER 2: THE CHEMISTRY OF LIFE The first job of a biologist is to understand the chemistry of life. 2-1 The Nature of Matter A. Atoms  ___________= the basic unit of matter (has volume and mass; solid, liquid, gas, and plasma)   Atoms are made Atoms subatomic particles called protons, neutrons, and electrons

4. = protons - = neutrons - = electrons - _______________= center of an atom. Home to protons and neutrons. Carbon Atom Positively charged 1 amu No charge 1 amu Electronegative charge 1/1840 amu electrons travel in regions outside the nucleus called orbitals Nucleus If the # of _________ = # of _________ the atom is _____________ (no overall charge) Ex. 6 protons = ++++++ 6 electrons = ------ protons electronsneutral

5. B B. Elements  Elements=  More than _____known kinds;  Found on the 100 2 dozen are common in living organisms pure substances that consists entirely of one type of atom Periodic table

6. Reading the Periodic Table Example: The element Carbon (only made of carbon atoms) ____________ usually 1-2 letters _______________= # Protons + # neutrons in an atom; the average of one elements isotopes ____________ of the element Atomic number = SYMBOL MASS NUMBER NAME Number of protons in an atom; different for each element Isotopes are the various forms of an atom that differ based on the number of neutrons in the nucleus such as C 14. The isotopes that differ from the most common form are often radioactive or unstable.

7. C. Chemical Compounds 1. Chemical compound= Example: Sodium Chloride = Table salt Forms when sodium and chlorine combine in a 1:1 ratio 2. Chemical formula= Example: Sodium Chloride= NaCl 3. ____________________________ of a molecule Example: = white crystalline solid = a soft silvery metal that reacts explosively with water = poisonous greenish gas a substance formed by the combination of 2 or more elements in definite proportions. a short hand that shows chemical composition Chemical properties NaCl Na Cl

8. D.Chemical Bonds Atoms in compounds are Involves the  2 main types of bonds are: ___________ and _________ held together by links called chemical bonds. interaction of electrons covalent ionic

9. 1. Ionic Bonds a. b. ion= are formed by the transfer of one or more electrons from one atom to another. an atom that has a positive or negative charge as a result of gaining or losing electrons.

10. FORMING AN IONIC BOND Sodium atom (Na)Chlorine atom (Cl)Sodium ion (Na + )Chloride ion (Cl - ) Transfer of electron Protons +11 Electrons-11 Charge Protons +17 Electrons-17 Charge Protons +11 Electrons-10 Charge Protons +17 Electrons-18 Charge Section 2-1 Figure 2-3 Ionic Bonding 0 0 +1 c. Opposite charges attract creating a bond between the ions

11. 2. Covalent Bonds a. formed by the b. Sharing means c. atoms sharing 2 electrons= __ electrons=double bond 6 electrons= d. _________________= The smallest unit of most chemical compounds (those joined with covalent bonds) sharing of electrons between 2 atoms. that the moving electrons are actually traveling in the orbitals of both atoms. single bond 4 triple bond Molecule

12. 2-2 Properties of Water- Refer to reader ’ s guide 2-3 Carbon Compounds A. The Chemistry of Carbon 1. Carbon has ________________ which means carbon can form _________________ 2. Living organisms are made up of molecules that consist 3. Carbon can bond with itself forming 4 valence electrons 4 covalent bonds. of carbon, hydrogen, oxygen, phosphorus, nitrogen and sulfur. chains of unlimited length and form, rings, and complex structures.

13. B. Macromolecules 1. Macromolecules= 2. Polymerization= 3. Monomers= 4.  The _____ groups of organic compounds found in living things are: are giant molecules consisting of 1000+ smaller molecules. process of joining small molecules to form large molecules small units that form polymers (large molecules) 4 carbohydrates lipids nucleic acids proteins

14. Made of Example Function Monomer Carbohy- drate C,H,O 1:2:1 Glucose C 6 H 12 O 6 1.Stores Energy - animals = -plants = 2. Structural Purposes - - Monosaccharide = Mono + mono +mono= Lipids Mostly C, H Very little O 1. Stores Energy 2. Form cell membranes 3.Waterproof coverings 4. Chemical messengers 1 glycerol 3 fatty acids Saturated- Unsaturated- GLYCOGEN STARCH PLANT CELL WALLS (CELLULOSE) CHITIN (INSECT EXOSKELETON) SINGLE SUGAR POLYSACCHARIDE FATS OILS WAXES STEROIDS NO DOUBLE BONDS IN FATTY ACID AT LEAST ONE DOUBLE BOND

15. Nucleic acids CHOPNCHOPN Stores and transmits hereditary information Nucleotide= 1. 2. 3. ProteinsCHONCHON methionine Shape determines function 1. 2. pump small molecules in and out of the cell 3. aids in cell movement Amino acids Made of ExampleFunction Monomer DNA/RNA 5-C SUGAR PHOSPHATE GROUP NITROGENOUS BASE 20 KINDS HELPS CONTROL RATE OF REACTIONS (ENZYMES)

16. IQ Quiz: Chapter 2 1.What kind of compounds did we test in the lab? 2.What chemical was used to test for simple sugars? 3.What was a positive result? 4.If we want to see if peanuts have fat in them what could we do? 5.How do we know if it is positive? 6.What did copper sulfate and sodium hydroxide test for? 7.What was a positive result? 8.If I had a bowl of cereal and Iodine fell into my cereal and turned a blue-black color what do I know is in my cereal? 9.Name a food that had more than 1 compound in it? (tested positive for more than 1 test) 10. What are the four most common elements in living things?

17. 2-4 Chemical Reactions and Enzymes A. Chemical Reactions =process that changes, or transforms one set of chemicals into another. Always involves changes in chemical bonds. 1. Reactants= 2. Products= EXAMPLE: HCl H + Cl elements or compounds that enter a reaction elements or compounds produced by a reaction

18. B. Energy in Reactions Activation Energy= C. Enzymes 1. Catalyst= energy that is needed to get a reaction started a substance that speeds up the rate of a chemical reaction without changing itself.

19. A E without enzyme A E with enzyme reactants products Reaction with no enzyme Reaction with an enzyme 2. Catalysts ___________________________in a chemical reaction. lower the activation energy

20. 3. ______________ are ___________________ that speed up favorable (spontaneous) reactions. 4. Enzymes _____________ chemical reactions that take place in cells. 5. Enzymes are Enzymesbiological catalysts speed up very specific D. Enzyme Action 1. The Enzyme-Substrate Complex a. Enzymes provide a site where reactants can be brought together to react (increasing the rate of reaction by reducing the activation energy)

21. Glucose Substrates ATP Substrates bind to enzyme Substrates are converted into products Enzyme (hexokinase) ADP Products Glucose-6- phosphate Products are released Section 2-4 Figure 2-21 Enzyme Action Active site= Enzyme Activity Site on the enzyme where the substrate attaches The reactants of a catalyzed reaction Enzyme- substrate complex

22. b. Enzymes are not 2. Regulation of Enzyme Activity - Enzyme activity depends on environmental factors such as:  (enzymes in the stomach function best around pH=2)  (human enzymes function best around 37°C) consumed in the reaction; after products are formed, the enzyme is recycled. pH temperature -Ionic conditions (coenzymes) -Substrate concentration (greater the concentration the greater the rate of the reaction)

23. Warm-up questions 1. Describe the difference between ionic and covalent bonds. Provide an example for each.

24. Warm-up 1. What are the 4 organic macromolecules which make up living organisms. 2. What are the monomers (building blocks) to these macromolecules.

25. Warm-up 1. What is a catalyst? 2. What are enzymes? 3. How do catalyst work? 4. What affects the activity of an enzyme?