Matter is recycled and rearranged for living organisms Living matter is made up of different substances. Example of substances: pure CO 2, glucose, pure salt, H 2 O….. CO 2 glucose

Atoms, Molecules and Compounds

Atoms - Smallest unit of an element (with properties of that element) Nucleus - dense center containing: –Protons - positively charged particles –Neutrons - particles with no charge Electrons (e - ) - small, negatively charged particles that orbit nucleus in clouds or shells (2, 8, 8) –Valence e - - found in outermost energy level How many total e - ? How many valence e - ? What element?

Lewis Dot Diagrams The inner shells are not involved in bonding Carbon is in group 14, so that means 4 valence electrons We often write the element symbol and only the valence electrons

You try… What does the Lewis dot diagram look like for Oxygen? What does the Lewis dot diagram look like for Sodium? Hydrogen? How about Lithium? Why are they all the same? NaH Li

Ions = electrically charged matter Ions form when electrons are lost or gained. Ionic bonds form when a positive ion is attracted to a negative ion. OIL RIG Oxidation is losing, Reduction is gaining

Covalent bond = two atoms sharing electrons “Strong” Relatively stable H, O and N can readily form covalent bonds with C.

Chemical Equations 2H 2 O 2 → 2H 2 O + O 2 Reactants Hydrogen peroxide Products Water & Oxygen Yield sign coefficient Subscripts coefficient How many hydrogen atoms are in the reactants? How many hydrogen atoms are in the products? How many water molecules are produced? How many molecules of hydrogen peroxide are broken down?

Chemical reactions 6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 Lead to changes in substance or matter. Occurs when electrons are transferred between two atoms (lost, gained or shared)

The 17 essential elements in plants (autotrophs)… CHOPKINS Ca Fe Mg B Mn Cu Zn Mo Cl Carbon, Hydrogen, Oxygen, Phosphorous, Potassium, Iodine, Nitrogen, Sulfur, Calcium, Iron, Magnesium, Boron, Manganese, Copper, Zinc, Molybdenum, Chlorine C HOPKINS Café Managed by my cousin Mo Cline

96% of living matter: C, H, O, and N 4% of living matter: Ca, K, P, S, Na, Cl, Mg, Fe, and trace elements

Hydrogen Bonding Weak bonds between a hydrogen of one molecule to an adjacent negative molecule Ex: attraction between water molecules.

Properties of Water

Check for Understanding What is the name of the compound in the bottle? What is the molecular formula? What is the structural formula? How many molecules of the substance are in the bottle? How would you calculate this?

Water The universal solvent in living things which makes up over 90% of cells and the majority of Earth

Why water works well in living things 1.Water is Polar and is really good at dissolving substances 2.Water is needed for all cellular chemistry 3.Water molecules adhere to some things 4.Water molecules stick together 5.Water molecules form surface tension 6.Ice floats 7.Water has a high specific heat

Universal solvent Water is a solvent (it dissolves stuff for living things) Water can dissociate (break apart) most ionic compounds such as salts. Solutes + Solvent = Solutions

The Lewis dot structure for water shows the electron from hydrogen and an electron from oxygen being shared in a covalent bond. The other four valence electrons in oxygen are in pairs at the bottom. The lines are a short-hand version of the two dots representing the covalent bonds.

+ - +

Polar or angular molecules have a non-linear shape. For example, water (H 2 O), has an angle of about 105°. A water molecule has two pairs of bonded electrons and two unshared lone pairs. Water is a Polar molecule

Create a Polar Water molecule On page 2 (left facing page side) of your learning journal and using construction paper, create a water molecule. Try to mimic the 105° angle using a protractor if possible. Show the covalent bonds as solid lines between the Oxygen and the Hydrogens.

The water molecule is Polar because…… ___________________________________ ___________________________________ ___________________________________ Page

Hydrogen Bonding Hydrogen bonds show the attraction between …. __________________________________ __________________________________ Page 3

Polarity Water molecules are polar. Polarity: one end of the molecule is positively (+) charged and the other end negatively (-) charged Polarity causes hydrogen bonding between water molecules

Water molecules are attracted to each other. Water molecules “stick” together. Cohesion Hydrogen Bonds

Cohesion causes Surface Tension Surface Tension Water molecules tend to stick together, forming a sort of “skin” Some animals can use this “skin” as surface on which it can walk. Water strider spider

What properties of water makes a belly flop hurt so bad? vFX-0&feature=fvsrhttp:// vFX-0&feature=fvsr Surface Tension

Capillary action in Plants

Adhesion Water molecules are attracted to surfaces that have charges (hydrophilic). Water molecules are repelled from surfaces that have no charge (hydrophobic).

Density Water becomes less dense (more space between molecules) when it freezes.

Properties of water’s density Ice floats, creating buffer from cold air, enabling organisms to still survive underneath the frozen surface.

Why is carbon the basis for life? It has 4 electrons in its outer (valence) electron shell. Octet rule: The most stable elements have 8 electrons in its outer shell, with few exceptions. Carbon forms 4 covalent bonds to fulfill the octet rule. Therefore, Carbon is really good at forming rings and chains

MethaneAcetyleneButadieneBenzeneIsooctane Section 2-3 Some Carbon Compounds

Organic compounds Always contain carbon (carbon can bond with many other elements) Small units called monomers join together to form polymers

Making polymers Think of molecules as “mers” When 2 monomers join, they form dimers. Adding more monomers form polymers.  1 “mer” = monomer  2 “mers” (mer+mer) = dimer  3 or more “mers” (mer+mer+mer+mer) = polymer

4 Important carbon polymers & complex molecules 1.Carbohydrates 2.Proteins 3.Lipids 4.Nucleic acids

Dehydration synthesis - Joining monomers into polymers while taking away water molecules A-OH + B-H  AB + H 2 O Dehydrate – to take away water Synthesis – to make

Carbohydrates – sugars, starch, cellulose, chitin Function: quick energy (4 calories per gram) Building blocks: Monosaccharides or simple sugars like glucose C 6 H 12 O 6 Carbohydrates provide cellular energy Cell Membrane functions and support Examples: –Monosaccharides (glucose, fructose, etc) –Disaccharides (sucrose, lactose, etc) –Polysaccharides (starch, cellulose, glycogen, chitin)

Starch Glucose Section 2-3 Starch

Proteins – used for structure and function Purpose: can be used for energy (4 calories per gram) but mostly used for cell structure and metabolism (enzymes) Building blocks: amino acids (20) held together by peptide bonds Sometimes very large, complex molecules

General structureAlanineSerine Section 2-3 Amino groupCarboxyl group Amino Acids

ATP Synthase

Antibodies Hormones Hemoglobin Enzymes Muscle fibers

Lipids – fats, oils, waxes, sterols Function: long term stored energy (9 calories per gram) Provides insulation & cushioning Does NOT have monomer/polymer structure Examples: –Saturated (animal fats) –Unsaturated (plant oils) –phospholipids are the basic structure of cell membranes. –Steroids are signal chemicals to initiate a process in the body

Examples of Sterols cholesterol steroids estrogen testosterone Click on the testosterone molecule

Lipid Structure

Some examples of lipids

Lipids are a vital component of cell membranes

Nucleic acids Functions: store & translate hereditary information. Building blocks: Monomers of nucleotides (sugar, phosphate, base) Examples: –DNA (stores code) –RNA (translates code to protein)

Parts of a Nucelotide Phosphate Sugar Nitrogen containing Base

What does DNA do? DNA does NOT govern cell activity directly!! “DNA is the code for the making of proteins used for structure and function”.

The 4 Bases found in DNA

The 4 Bases found in DNA as Nucleotides

DNA Structure

Organic macromolecule Monomer (building block) Polymer (Types) Carbohydrates 4 calories per gram Monosaccharide (ex: Glucose) Polysaccharides (ex: sugars, starch, cellulose, glycogen, chitin, etc.) Proteins 4 calories per gram Amino acidsStructural proteins and enzymes Lipids 9 calories per gram Glycerol and fatty acids Fats, oils, waxes, sterols Nucleic acids Heredity information NucleotidesDNA, RNA