1 Chemistry Basics

2 Compounds Most elements do not exist by themselves Readily combine with other elements in a predictable fashion

3 A compound is a pure substance made up of atoms of two or more elements The proportion of atoms are always fixed Chemical formula shows the kind and proportion of atoms of each element that occurs in a particular compound

4 Molecules are the simplest part of a substance that retains all of the properties of the substance and exists in a free state Some molecules are large and complex

5 Energy and Chemical Reactions Living things undergo thousands of chemical reactions as part of the life process

6 Many are very complex involving multi-step sequences called biochemical pathways Chemical equations represent chemical reactions Reactants are shown on the left side of the equation Products are shown on the right side

Macromolecule Equations: Reactants and Products ____________________: sunlight 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 ______ + ______________ + _________ _____________________: C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP ______ + ____________ + ______ + _____ 7

Photosynthesis - sunlight 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 The process used by plants, algae, and some bacteria to create sugar (energy) from sunlight 8

Cellular Respiration The process used in the cells mitochondria to create energy from sugar C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP 9

ATP - ENERGY What is ATP? Energy used by all Cells Adenosine Triphosphate Organic molecule containing high-energy Phosphate bonds What Does ATP Do for You? It supplies YOU with ENERGY! 10

ATP structure 11

12 Enzymes are an important class of catalysts in living organisms Mostly protein Thousands of different kinds Each specific for a different chemical reaction

13 Enzyme Structure Enzymes work on substances called substrates Substrates must fit into a place on an enzyme called the active site Enzymes are reusable!

14 Solutions A solution is a mixture in which 2 or more substances are uniformly distributed in another substance

15 Solute is the substance dissolved in the solution Particles may be ions, atoms, or molecules Solvent is the substance in which the solute is dissolved Water is the universal solvent

16 Biochemistry of Cells

Organic vs. Inorganic Molecules Organic Molecules or Compounds: Living things ALL organic molecules contain the element CARBON!!! Anything that is considered “biotic” Examples: Inorganic Molecules or Compounds: All non-living or never were living things Anything that is considered “abiotic” Examples: 17

18 Uses of Organic Molecules Americans consume an average of 140 pounds of sugar per person per year Cellulose, found in plant cell walls, is the most abundant organic compound on Earth

19 Uses of Organic Molecules A typical cell in your body has about 2 meters of DNA A typical cow produces over 200 pounds of methane gas each year

20 Water About percent of an organism is water Water is used in most reactions in the body Water is called the universal solvent

21 Water Properties Polarity A molecule with positive and negative charged ends has polarity and is called a polar molecule. The water molecule’s polarity allows it to bond with adjacent water molecules. The positively charged hydrogen end of one water molecule attracts the negatively charged oxygen end of another water molecule.This bond between water molecules is called a hydrogen bond.

22 Water Properties CohesivenessAdhesiveness Cohesion/Adhesion. Because hydrogen bonds attract water molecules to each other, they tend to stick together. This is cohesion. Water also sticks to other materials due to its polar nature. This is adhesion.

23 A skin-like surface formed due to the polar nature of water. Surface tension is water’s resistance to objects attempting to penetrate its surface. Surface Tension

24 Water Properties Surface Tension

Draw and label a molecule of water: 25

26 Giant Molecules - Polymers Large molecules are called polymers Polymers are built from smaller molecules called monomers Biologists call them macromolecules

27 Examples of Polymers Proteins Lipids Carbohydrates Nucleic Acids

28 Most Macromolecules are Polymers Polymers are made by stringing together many smaller molecules called monomers Nucleic Acid Monomer

29 Linking Monomers Cells link monomers by a process called dehydration synthesis (removing a molecule of water) This process joins two sugar monomers to make a double sugar Remove H Remove OH H 2 O Forms

30 Breaking Down Polymers Cells break down macromolecules by a process called hydrolysis (adding a molecule of water) Water added to split a double sugar

31 Macromolecules in Organisms There are four categories of large molecules in cells: Carbohydrates Lipids Proteins Nucleic Acids

32 Carbohydrates Carbohydrates include: Small sugar molecules in soft drinks Long starch molecules in pasta and potatoes

33 Monosaccharides: Called simple sugars Include glucose, fructose, & galactose Have the same chemical, but different structural formulas C 6 H 12 O 6

34 Monosaccharides Glucose is found in sports drinks Fructose is found in fruits Honey contains both glucose & fructose Galactose is called “milk sugar”

35 Isomers Glucose & fructose are isomers because they’re structures are different, but their chemical formulas are the same

36 Cellular Fuel Monosaccharides are the main fuel that cells use for cellular work

37 Disaccharides A disaccharide is a double sugar They’re made by joining two monosaccharides Involves removing a water molecule (dehydration)

38 Disaccharides Common disaccharides include:  Sucrose (table sugar)  Lactose (Milk Sugar)  Maltose (Grain sugar )

39 Disaccharides Sucrose is composed of glucose + fructose Maltose is composed of 2 glucose molecules Lactose is made of galactose + glucose GLUCOSE

40 Polysaccharides Complex carbohydrates Composed of many sugar monomers linked together Polymers of monosaccharide chains

41 Starch Starch is an example of a polysaccharide in plants Plant cells store starch for energy Potatoes and grains are major sources of starch in the human diet

42 Glycogen Glycogen is an example of a polysaccharide in animals Animals store excess sugar in the form of glycogen Glycogen is similar in structure to starch

43 Cellulose Cellulose is the most abundant organic compound on Earth It forms cable-like fibrils in the tough walls that enclose plants It is a major component of wood It is also known as dietary fiber

44 Dietary Cellulose Most animals cannot derive nutrition from fiber They have bacteria in their digestive tracts that can break down cellulose

45 Sugars in Water Simple sugars and double sugars dissolve readily in water They are hydrophilic, or “water- loving”

46 Lipids Lipids are hydrophobic –”water fearing” Includes fats, waxes, steroids, & oils Do NOT mix with water

47 Function of Lipids Fats store energy, help to insulate the body, and cushion and protect organs

48 Types of Fatty Acids Unsaturated fatty acids have less than the maximum number of hydrogens bonded to the carbons (a double bond between carbons ) Saturated fatty acids have the maximum number of hydrogens bonded to the carbons (all single bonds between carbons )

49 Triglyceride Monomer of lipids Composed of Glycerol & 3 fatty acid chains Glycerol forms the “backbone” of the fat

50 Fats in Organisms Most animal fats have a high proportion of saturated fatty acids & exist as solids at room temperature (butter, margarine, shortening)

51 Fats in Organisms Most plant oils tend to be low in saturated fatty acids & exist as liquids at room temperature (oils )

52 Fats Dietary fat consists largely of the molecule triglyceride composed of glycerol and three fatty acid chains

53 Steroids The carbon skeleton of steroids is bent to form 4 fused rings Cholesterol is the “base steroid” from which your body produces other steroids Estrogen & testosterone are also steroids

54 Proteins Proteins are polymers made of monomers called amino acids All proteins are made of 20 different amino acids linked in different orders Proteins are used to build cells, act as hormones & enzymes, and do much of the work in a cell

55 Four Types of Proteins Structural Contractile Storage Transport

56 Linking Amino Acids Cells link amino acids together to make proteins The process is called dehydration synthesis Peptide bonds form to hold the amino acids together

57 Proteins as Enzymes Many proteins act as biological catalysts or enzymes Thousands of different enzymes exist in the body Enzymes control the rate of chemical reactions by weakening bonds, thus lowering the amount of activation energy needed for the reaction

58 Enzymes Their folded conformation creates an area known as the active site. Enzymes are globular proteins. The nature and arrangement of amino acids in the active site make it specific for only one type of substrate.

59 Enzyme + Substrate = Product

60 How the Enzyme Works Enzymes are reusable!!!

61 Nucleic Acids Store hereditary information Contain information for making all the body’s proteins Two types exist --- DNA & RNA

62 Nucleic Acids Nucleic acids are polymers of nucleotides

63 Bases Each DNA nucleotide has one of the following bases: Thymine (T)Cytosine (C) Adenine (A)Guanine (G) – Adenine (A) – Guanine (G) – Thymine (T) – Cytosine (C)

64 Nucleotide Monomers Form long chains called DNA Nucleotides are joined by sugars & phosphates on the side

65 DNA Two strands of DNA join together to form a double helix

66 RNA – Ribonucleic Acid Ribose sugar has an extra –OH or hydroxyl group It has the base uracil (U) instead of thymine (T) Nitrogenous base (A,G,C, or U) Sugar (ribose) Phosphate group Uracil

67 Nucleic Acids

68 Summary of Key Concepts

69 Macromolecules

70 Macromolecules

71 End