 Anything that has mass and occupies space  Some matter is changed chemically to produce energy  Energy used to carry out cell activities

 Exists in 3 states  Solid – definite volume, definite shape  Liquid – definite volume, indefinite shape  Gas – indefinite volume, indefinite shape

 Chemical and Physical Properties  Physical Properties – physical appearance or characteristic of a substance  Color  Boiling or Melting Point  Hardness  Chemical Properties – how one kind of matter reacts with other matter  Burning of a substance

 Physical and Chemical Changes  Physical Changes – appearance changes, matter does not  Change of State  Freezing – from liquid to solid  Melting – from solid to liquid  Evaporation – from liquid to gas  Condensation – from gas to liquid  Sublimation – from solid to gas  Change in size – cutting paper  Chemical Change – matter changes  Iron reacts with oxygen to produce rust  Law of Conservation of Matter – matter is neither created nor destroyed, only changes form

 Atom – tiny unit of matter  Composed of:  Protons - + charge, 1amu, in nucleus  Neutron – no charge, 1amu, in nucleus  Electron - - charge, 0 amu, in electron cloud

 Element – Substance containing only one type of atom  Atoms of same elements have the same number of protons – called Atomic Number  Hydrogen – 1 proton  Oxygen – 8 protons  Sum of protons + neutrons determines Atomic Mass Number  Isotopes – atoms that have the same number of protons but different numbers of neutrons  Number of electrons = Number of protons; result atom is electrically neutral

 Elements are arranged according to atomic number in the Periodic Table

Element Symbols 1 st one or two letters of English name Hydrogen -H Helium -He Others from Latin or foreign language names SilverAgArgenitum (Latin) TungstenWWolfran (German) 1 st letter always capitalized, 2 nd is lower case

Atoms want to be stable, want a complete outer energy level Combine with other elements; both become stable Compound – substance formed when 2 or more elements bond chemically

Stability by sharing or transferring electrons Covalent Bond – electrons are shared Molecule – bonded set of atoms Ionic Bond – electrons are transferred Ion – electrically charged atom Negative Ion – gain electrons Positive Ion – loses electrons Bond forms due to attraction of oppositely charged ions

Covalent Bonds – Water (H 2 O)

Ionic Bonds – Sodium Chloride (NaCl)

Chemical Formula – Expression of chemical makeup of a compound Shows kinds and number of atoms H 2 O – 2 atoms hydrogen; 1 atom oxygen Coefficients show number of molecules 2H 2 O – 2molecules; 4 atoms H; 2 atoms O

Composed of 2 or more substances that can be separated by physical means Homogeneous – every part looks same Heterogeneous – some sections look different Types Solution Suspension Colloid

Solution Homogeneous mixture where one substance is dissolved in another Solute – Substance dissolved Solvent – Substance doing the dissolving

Suspension Heterogeneous mixture of substances larger than molecules or ions Particles may settle Some stay suspended; cloudy appearance Example - Blood

Colloid Homogeneous mixture with particles larger than in solution but smaller than a suspension Clusters of atoms, ions or molecules Examples – Gelatin, Homogenized Milk

Most atoms in Human Body Hydrogen Oxygen Carbon Nitrogen

Inorganic Compounds Primarily composed of elements other than Carbon Organic Compounds Contain the element Carbon

Most abundant inorganic compound in living organisms Composed of Hydrogen and Oxygen

Universal Solvent – dissolves many substances due to polarity of water Dissolves ionic compounds to produce ions called electrolytes Doesn’t dissolve covalent compounds very well

Dissociates to form H + and OH - ions Both are equal in distilled water Gives us the pH scale Below 7 – acidic Above 7 – alkaline 7 - neutral

Polarity of water Causes hydrogen bonding – bond between H of one and O of another. Results in water’s unique properties Boiling and Freezing Points Cohesion – attracted to other water molecules – water droplets Adhesion – attracted to other similar molecules – allows movement of water in plants

Inorganic even though it contains carbon Source of Carbon and Oxygen in organic compounds by way of photosynthesis

Contain the element Carbon Has 4 electrons in outer energy level Can form 4 bonds – either with other carbons or other elements

Originally believed to have to come from living organisms Many have been synthesized

Often described by structural formulas Show kinds of atoms Show number of atoms Show how atoms are attached to each other

Organic Compound important to Life Carbohydrates Proteins Lipids Nucleic Acids

Processes (reactions) important to organic compounds Dehydration Synthesis Production of a more complex molecule from 2 or more simpler molecules by removing a water molecule Hydrolysis Breakdown of a more complex molecule into simpler molecules by the addition of a molecule of water – usually during digestion

Composed of Carbon, Hydrogen, and Oxygen Hydrogen: Oxygen ratio always 2 to 1 Used for energy source, structure, and energy storage Classes Monosaccharides Disaccharides Polysaccharides

Monosaccharides – single sugars Most have formula C 6 H 12 O 6 –different structures Examples – glucose, fructose, galactose Glucose – food product of photosynthesis

Disaccharides – double sugars Composed of 2 monosaccharides that combine by dehydration synthesis Molecular formula – C 12 H 22 O 11 Examples Sucrose (Table Sugar) – Glucose + Fructose Lactose (Milk Sugar) – Glucose + Galactose

Polysaccharides – many sugars Made of many monosaccharides that combine during a series of dehydration syntheses Types Cellulose – structural compound in plants Starch – energy storage in plants Glycogen – energy storage in animal livers; called “animal starch”

Composed of Carbon, Hydrogen, Oxygen, and Nitrogen; sometimes Sulfur Made up of 20 different Amino Acid joined together by dehydration synthesis reactions. Peptide Bonds join the amino acids – amino group of one amino acid attaches to carboxyl group of another amino acid

Used to build and repair cells; also function as enzymes. Types Dipeptide – 2 amino acids Polypeptide – many amino acids

Amino Acid Structure 3 basic parts around a central Carbon Amino Group – NH 2 Carboxyl Group – COOH R-Group – a simple H or group of Carbon and Hydrogen atoms Hydrogen forms the 4 th bond.

Enzyme - protein molecule that acts as an organic catalyst – changes the rate of chemical reaction Acts on a Substrate – Material to be changed Often described as a “Lock and Key” operation Lock – substrate Key - enzyme

Contain Carbon, Hydrogen, and Oxygen Larger number of Hydrogen atoms and lower number of Oxygen atoms than carbohydrates Insoluble in water Most composed of Fatty Acids Primary function is energy storage but help form cell membranes

Fatty Acids Large straight chain hydrocarbon with a carboxyl group at one end Carboxyl Group – Hydrophilic Hydrocarbon Chain – Hydrophobic

Saturated Fatty Acid Unsaturated Fatty Acid

Kinds Triglycerides – 3 fatty acids bonded to a glycerol by dehydration synthesis Oil – Liquid at room temperature Fat – Solid at room temperature Wax – Long fatty acid bonded to long alcohol Steroids – Rings of 4 Carbons; hormones, nerve tissue, some plant and animal poisons

Triglyceride

Phospholipids

Complex molecules that store and transmit important information about the cell Involved with transmission of characteristic during cell reproduction Types Deoxyribonucleic Acid – DNA Ribonucleic Acid – RNA

DNA and RNA – composed of thousands of nucleotides Nucleotides – composed of 3 parts formed by dehydration synthesis Parts 5-Carbon Sugar – Ribose or Deoxyribose Phosphate Group Nitrogen Base – Guanine, Cytosine, Adenine, Thymine, or Uracil

Deoxyribonucleic Acid Stores information essential for cell activities Found mostly in the cell nucleus Ribonucleic Acid Stores and transfers information to make proteins