Learning Target 2 I can explain the structure and function of the 4 macromolecules within the body.

Why are organic compounds made of carbon? Able to form more bonds than most elements (4 covalent bonds) May form either single, double, or triple bonds (share more electrons) May form straight chains, branched chains, or rings Important enough to have its own chemistry - Organic Chemistry Often forms Hydrocarbons = Contains carbon and hydrogen atoms

Carbon Compounds may be saturated or unsaturated Molecules made of single carbon chains are most stable = saturated Molecules made of double or triple chains = unsaturated Molecules made of more than one double or triple = polyunsaturated Hydrogenation - Process by which unsaturated fats and hydrogen atoms combine to make saturated fats

Carbs Lipids Proteins Nucleic Acids Polymers Lipids Definition: A large molecule formed when many small molecules, typically called monomers or building blocks, bond together Large polymers are called macromolecules Four types of organic compounds/macromolecules are commonly found in the body: carbohydrates, lipids, proteins and nucleic acids. Organic Compound SCAVENGER HUNT! Proteins Nucleic Acids

I can explain why chemical reactions occur in the cell. Learning Target 4 I can explain why chemical reactions occur in the cell.

Chemical Reactions When do they happen? Chemical reactions occur constantly in cells Why do they happen? To form new molecules for growth and repair Involved in energy release, storage or use All the chemical reactions in your body = Metabolism How do they happen? A chemical reaction occurs when chemical bonds are broken and elements are rearranged. Sharing or transfer of outer electrons forms a bond Bonds break when elements or compounds bump into each other with enough energy to break them.

Where does the energy come from? Energy is required to break bonds apart and is released when new bonds are formed. (It takes energy to break something) The energy required is supplied by ATP (adenosine triphosphate). When the 2nd and 3rd phosphate groups of ATP are broken apart, energy is released. Animation: http://www.biologyinmotion.com/atp/

Chemical Equations Represent chemical reactions Involve reactants (on the left side) and products (right side) Example: 2H2O -------------> 2 H2 + O2 This reaction involves 4 hydrogen atoms and 2 oxygen atoms 2 molecules of water react to form 2 H2 and 1 O2 Must be balanced = same number and types of atoms on both sides

Type of Bond = Ionic bond (Exp = NaCl) Giving or losing electrons in outer level (transfer of electrons) Results in charged particles called ions Ions then attract = ionic bond These bonds break apart in water and conduct electricity. Form ionic compounds

Type of Bond = Covalent bond (Exp = H2O) Atoms share electrons to fill outer shell or level 2 electrons shared = single bond, 4 electrons shared = double bond, 6 electrons shared = triple Form Molecular Compounds

Polar vs Non-Polar Covalent Bonds Unequal sharing of electrons A slightly positive and a slightly negative end Dissolve ionic compounds and other polar molecules Also dissolve in water Example = H2O Non-polar covalent Bonds Equal sharing of electrons No differences in charges Do not dissolve in water Example = O2

Hydrogen bonds occur between some molecules, including water molecules Intermolecular forces between some polar covalent molecules containing hydrogen Attraction between slightly pos. and slightly neg. ends of some molecular compounds Much weaker than ionic or covalent bonds (not a true chemical bond because it is between molecules) Provides force between water molecules and help shape in large molecules

Water’s Properties due to Polarity/H-bonds Cohesion - Water molecules stick to each other (droplets) Adhesion - Water molecules stick to other surfaces (water on window) Capillary Action - Water molecules can move against gravity up small tubes (roots of plants) Surface Tension – Water molecules at the surface attract more to minimize surface area (insects can walk on water) Water molecules attract due to positive end of one molecule attracting to negative end of other molecule (polarity) Video: https://www.youtube.com/watch?v=ASLUY2U1M-8

Learning Target 5 I can describe what factors affect enzymes and their role in chemical reactions.

Chemical Reactions are assisted by Enzymes. Enzymes = Biological catalysts that lower the activation energy and allow the reactions to occur more quickly. Each reaction needs its own enzyme (like a lock and key) and thus your bodies has thousands of different enzymes. Video (take notes): https://highered.mheducation.com/sites/0072495855/stu dent_view0/chapter2/animation__how_enzymes_work.ht ml

What factors affect enzyme action? Temperature (reason Siamese cats have brown ears and noses) pH (enzymes in your stomach work at a lower pH) Enzyme concentration (more enzymes = increase reaction rate if substrate is in excess) Substrate concentration (more substrate = typically increases reaction rate to a point)