2.  http://www.youtube.com/watch?v=tpBA mzQ_pUE http://www.youtube.com/watch?v=tpBA mzQ_pUE

3.  Living things consist of atoms of different elements  Everything is made of very small particles  Atoms: smallest basic unit of matter Millions of atoms could fit in the period at the end of a sentence

4.  Atoms consist of three smaller particles Protons: positive charge Neutrons: no charge Electrons: negative charge  Protons and Neutrons make up the atomic nucleus  Electrons surround this dense center

6.  An atom has an equal number of protons and neutrons  Element: one particular type of atom that cannot be broken down into simpler substances by ordinary chemical means Examples of elements: hydrogen, oxygen, aluminum, gold Atoms of different elements have a different amount of protons

8.  Electrons in atoms determine its properties  Electrons move around the nucleus in energy levels  Atoms are most stable when they have a full outermost energy level

9.  There are about 91 elements that naturally occur on earth 25 are found in organisms 96 percent of human mass is made of 4 elements  carbon: C  oxygen: O  Nitrogen: N  Hydrogen: H The other 4 percent are trace elements: very small amounts but are necessary for survival

10.  Substance made of atoms of different elements bonded together in a certain ration Examples: carbon dioxide: CO 2, Water: H 2 O  A compounds properties are often different from the properties of the elements that make up the compound Example: Oxygen and Hydrogen are both gases. When combined they make water.

11.  1.Carbon ______________  2.Carbon Dioxide ______________  3.Water ______________  4.H ______________  5.CO 3 ______________  6.SiO ______________  7.O ______________  8.Ca ______________

12.  Ions form when atoms gain or loose electrons  Ion: atom that has gained or lost one or more elections  Gain or loss of electrons results in a full outermost energy level  An atom becomes an ion when it gains electrical charge

13.  Ions have certain properties: because of the charge Example: compounds consisting of only ions – ionic compounds- easily dissolve in water  Some ions can be positive or negatively charged  Ions usually form when electrons are transferred from one atom to another  Ionic bond: forms through the electrical force between oppositely charged ions

15.  Not all atoms easily gain or loose electrons  Some share pairs of electrons  Covalent bonds: form when atoms share a pair of electrons  Very strong bonds

17.  Molecule: two or more atoms held together by covalent bonds  Almost all substances that make up organisms (lipids to nucleic acids to water) are held together by covalent bonds

18. http://www.youtube.com/watch? v=aVmU3CLxvgU

19.  Water exists as a solid, liquid, and gas  Less dense as a solid than a liquid  Water is polar  Polar molecules have a region that is slightly positive and a region that is slightly negative

21.  Opposite charges interact to form hydrogen bonds  Hydrogen bonds: attraction between a slightly positive hydrogen atom and a slightly negative atom (often nitrogen or oxygen)  Part of DNA

22.  Much weaker then covalent bonds  3 important properties High Specific Heat: water resists change in temperature Cohesion: attraction amount molecules of a substance, provides surface tension Adhesion: attraction among molecules of different substances

23.  Many substances in the body dissolve in water  Solutions: mixture of substances that is the same throughout (homogenous mixture)  Solutions are made of 2 parts Solvent: substance that is present in greater amount and dissolves another substance Solute: substance that dissolves in a solvent  EXAMPLE: water and sugar  Water: Solvent  Sugar: Solute

24.  Amount of solute dissolved in a certain amount of solvent is a solution’s concentration  Blood Plasma is where many molecules dissolve: such as protein and sugar  Polar molecules dissolve in water because the attraction between the water molecules and the solute molecules are greater than the attraction among the molecules of the solute  Nonpolar substances (fats and oils) do not dissolve in water they lack a charged region and are not attracted to polar molecules

25.  acid: compound that releases a proton when it dissolves (H + increases)  base: compounds that remove H + from a solution  a solutions acidity is measured on the pH scale

26. 14: Basic 0: Acidic 7: Neutral  Examples:  Stomach acid: pH 2  Water: pH 7  Blood: pH 7.4  Bile: pH 8-9

28.  Different organisms need different pH for survival  Buffers regulate pH in organisms  Buffer: compound that can bind to an H + ion when H + concentration decreases

30.  Inorganic: contain any of Earth’s elements but rarely contain carbon and hydrogen together.  Organic: all organic compounds contain the elements carbon and hydrogen always!

31. 1. Water (H 2 O) ____________ 2. Methane (CH 4 ) ______________ 3. Carbon Dioxide (CO 2 ) ______________ 4. Salts (NaCl)_____________ 5. Sugar (C 6 H 12 O 6 ) _____________ 6. Ozone (O 3 )_________________

32.  Carbon is often called the building block of life  Each carbon atom has four unpaired electrons in its outer energy level  Carbon atoms can form up to four covalent bonds with four other atoms

33. Straight chains Branched chains Ring chains

34.  Many carbon based molecules are subunits of an entire molecule  Monomer: each subunit in the complete molecule  Polymer: large molecule (macromolecule) made of many monomers bonded together

36.  Molecules composed of carbon, hydrogen, and oxygen, and they include sugar and starches  Can be broken down to provide a useable source of chemical energy for cells  Major part of plant cell structure

37. Basic sugar formula = C 6 H 12 O 6 Carbon to Hydrogen ratio is always 1:2

38.  Monosaccharides:  most basic carbohydrates  (Building Blocks!!) Fructose: 6-carbon sugar in fruits Glucose: 6-carbon sugar made during photosynthesis (C 6 H 12 O 6 )

39.  Disaccharide: two sugars bonded together  (2 monosaccharides)  Examples: Maltose and Sucrose

40.  Polysaccharides:  many glucose molecules bonded together  (3 or more monosaccharaides) Examples: starches, glycogen, and cellulose  Starches: stored by plants  Glycogen: stored by animals  Cellulose: straight rigid structure (makes up cell wall)

43.  ENERGY!

44. Building Polymers Dehydration synthesis – atoms that make up water (H 2 O) are removed from the small molecules to bring them together

45. Simply add water! Hydrolysis – Literally means “splitting with water” Water replaces the bond holding molecules together

46.  Nonpolar molecules that include fats, oils, and cholesterol  Chains of carbon atoms bonded to oxygen and hydrogen atoms  Can be a source of usable energy for a cells  Can be part of a cell’s structure

47.  Fats and oils: store large amounts of chemical energy in organisms  Fats and oils contain glycerol bonded to fatty acids  Fatty acids: chains of carbon atoms bonded to hydrogen atoms  Many lipids contain 3 fatty acids bonded to a glycerol (triglycerides)

48.  Saturated fats: animal fats: max number of hydrogen possible  Unsaturated fats: oils: not saturated with hydrogen atoms  Animal fats are solid, plant fats are liquid

49. + =

50.  Cell membranes are made of phospholipids Consists of a glycerol, two fatty acids, and a phosphate group  Cholesterol: lipid with a ring structure

51.  Long term energy storage  Build cell membranes  Heat insulator of organisms

52.  Contain Nitrogen!  Polymer made of monomers called amino acids  Amino acids: molecules that contain carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur  Organisms use 20 amino acids to build proteins  Body makes 12 of these amino acids, the rest is from food you eat

53.  Amino acids are made of: Hydrogen atom Amino group (NH 2 ) Carboxyl group (COOH)

56.  Amino acids differ on their side groups (called R group)  Amino acids form covalent bonds (called peptide bonds)  Bonds form between amino group on one amino acid and carboxyl group on another  Linked to form chains called polypeptides  Proteins are one or more polypeptides

57.  Hormones  Enzymes  Making new cells  Transport materials  Help with immunity

58.  Polymers that are made of monomers called nucleotides  Made of a sugar, a phosphate group, and a base  Two types of Nucleic Acids: DNA and RNA  Only have one function Work together to make proteins

61.  Chemical reactions: change substances into different substances by breaking and forming chemical bonds

62.  Reactants: substances changed during a chemical reaction  Products: substances made by a chemical reaction   6CO 2 + C 6 H 12 O 6  6CO 2 + 6H 2 O  reactants direction products

63.  Bond energy: amount of energy that will break a bond between two atoms  Bonds between different types of atoms have different bond energies  Energy is released when bonds are formed

64.  The amount of energy that is released is equal to the amount of energy that breaks the same bond Example: energy is released when hydrogen and oxygen atoms bond to form water. The same amount of energy is needed to break apart a water molecule.

65.  Many reactions in living things are reversible  When a reaction takes place at an equal rate in both directions, the reactant and product concentrations stay the same  Equilibrium: reached when both the reactants and products are made at the same rate

66.  Added energy breaks chemical bonds  During chemical reactions both energy is used and made  Activation energy: amount of energy that needs to be absorbed for a chemical reaction to start

67.  Exothermic: chemical reaction released more energy than it absorbs

68.  Endothermic: Chemical reaction absorbs more energy than it releases

70.  Catalyst: a substance that decreases the activation energy needed to start a chemical reaction  This results in the same amount of product but requires less energy  Catalysts are not considered to be either reactants or products because catalysts are not changed or used up during a reaction

71.  Reactants can be found in low concentrations  Enzymes: catalysts for chemical reactions in living things  Lower the activation energy and increase rate of chemical reactions  Enzymes do not affect chemical equilibrium

72.  Enzymes just change the amount of time needed Example: Amylase – protein in saliva that breaks down starch to simple sugars  Almost all enzymes are protein

73.  Enzymes depends on structure to function properly  pH levels and temperature can effect an enzymes function when the structure changes, it can no longer function properly

74.  Enzyme structure is important because it allows specific reactants to bind  Substrates: specific reactants that an enzyme will work with  Substrates bond temporarily at active sites.  Lock and key model