BIology Ch. 4

• Chemistry that specializes in the study of carbon compounds.
• (i.e. simple molecules, such as methane CH₄, to colossal ones, such as proteins with thousands of atoms.)

• Organic molecules consisting of hydrogen and carbon only.
• (Hydrocarbons are major components of fossil fuel, consisting of partially decomposed remains of million-year old organisms. Hydrocarbon not prevalent in living organisms, but some molecules consists of them. Ex. Fat (long hydrocarbon tails attached to non-hydrocarbons) and petroleum do not dissolve in water (hydrophobic), because bonds are nonpolar carbon-to-hydrogen linkages.

compounds that have the same numbers of atoms of the same elements but different structures and hence different properties. 3 TYPES: Structural, Geometric, and Enantiomers.

same molecular formula but different in covalent arrangement of carbon skeletons (different covalent partners). Ex. 2 five carbon compounds have different structure; hence, different properties.

Same covalent partnerships, but they differ in their spatial arrangement.

• Isomers that are mirror images of each other.
• (Figure 4.7 carbon is called the asymmetric carbon because it is attached to four atoms/groups of atoms. These can be arranged diff. in space, which will have mirror images of each other.)

• Chemical group that affect molecular function by being directly involved in chemical reactions.
• (7 chemical groups most imp. in biological processes are the hydroxyl, carbonyl, carboxyl, amino,
• sulfhydryl, phosphate, and methyl groups.

• Structure: OH---- or HO-----, hydrogen bonded to an oxygen, in turn bonded to a Carbon skeleton of an organic molecule. (not confused with hydroxide ion, OH^-)
• Name of Compound: Alcohols

• Part of chemical group Hydroxyl. Specific names usually end in -ol.
• EX: Ethanol : alcohol presented in alcohol beverages.
• Functional Properties: polar as a result of electrons spending more time near the electronegative oxygen atom and can form hydrogen bonds with water molecules, helping dissolve organic compounds such as sugars.

• Structure: carbon atom joined to an oxygen atom by a double bond (leaving carbon to bond with 2 atoms).
• Name of Compound: Ketones: if the carbonyl group is within the carbon skeleton. Aldehydes: if carbonyl group is at the end of the carbon skeleton.

• Carbonyl Group. Ex. Propanal. (carbonyl group is at the end of the skeleton)
• Aldehydes and Ketones are structural isomers that may have different properties, as in the case for propanal and acetone.
• 2 Groups are also found in sugars, 2 major sugars: aldoses (containing an aldehyde) and ketoses (containing a ketone).

Carbonyl Group: Simplest Ketone is Acetone. (carbonyl group is in the middle of the carbon skeleton).

• Oxygen is double bonded to a carbon atom that is also bonded to a hydroxyl (---OH) group.
• Name of Compound: Carboxylic Acid or organic acids.

• Example: Acetic Acid: which gives vinegar its sour taste.
• Functional Properties:

• ---NH₂ consists of nitrogen atom bonded to 2 hydrogen atoms and to the carbon skeleton.
• (AMINES)

Ex. Glycine: because it also has a carboxyl group (Pg. 64 and Pg. 65) Study Diagram.