Topic 1:Chemicals of life 1.Molecules and Atoms 2.Water 3.Carbon and Other elements

3.Carbon and Other Elements 3.1 Organic Chemistry 3.2 Bonding with Carbon Carbon Chains Hydrocarbons Isomers 3.3 Functional Groups Hydroxyl Carboxyl Carbonyl Amino Sulfhydryl Phosphate

All living organisms are made up of chemicals based mostly on the element carbon, besides water

the study of carbon compounds carbon compounds can be simple or very complex

The Concept of Vitalism organic compounds arise only within living organisms disproven in 1953 when Miller synthesized the compounds in the laboratory

carbon has four valence electrons it can form four covalent bonds with a variety of atoms C

(a) Methane (b) Ethane (c) Ethene (ethylene) Molecular Formula Structural Formula Ball-and-Stick Model Space-Filling Model H H H H H H H H H H HH H H C C C CC CH 4 C2H6C2H6 C2H4C2H4 Name and Comments Carbon can make molecules of different length

Carbon can bond covalently to many different elements H O NC Hydrogen (valence = 1) Oxygen (valence = 2) Nitrogen (valence = 3) Carbon (valence = 4)

the skeletons of most organic molecules contain carbon carbon skeletons vary in length, shape, and type of bonds H H H H H H H H H H H HHH H H H H H H H H H H H H H H H H HH H H HH HHH H HH HH H H H H H H H C C CCC CCCCCCC CCCCCCCC C C C C C C C C C C C C H H H H H H H (a) Length (b) Branching (c) Double bonds (d) Rings Ethane Propane Butane 2-methylpropane (commonly called isobutane) 1-Butene2-Butene Cyclohexane Benzene HH HHH Carbon can make Chains and Rings

Hydrocarbons molecules consisting of only carbon and hydrogen methane ethane propane butane

Hydrocarbons are found in many of a cell ’ s organic molecules (a) A fat molecule (b) Mammalian adipose cells 100 µm Fat droplets (stained red)

Isomers molecules with the same molecular formula but different structures and properties H H HH H H H H HH H H H HH H H H H H H H H H H H H H CO 2 H CH 3 NH 2 C CO 2 H H CH 3 NH 2 XX X X C CCCC C C C C C C C C C C (a) Structural isomers (b) Geometric isomers (c) Enantiomers H

Structural Isomers molecules with the same chemical formula, but different arrangement of the atoms C 4 H 10 They have different physical properties, ex. Melting point

Geometric Isomers molecules with the same chemical formula, but atoms are arranged on different sides of a bond or ring

Enantiomers are important in the pharmaceutical industry. Caused by the presence of asymmetric carbon atoms L-Dopa (effective against Parkinson’s disease) D-Dopa (biologically inactive)

the chemically reactive groups of atoms within an organic molecule that give it its chemical properties CH 3 OH HO O CH 3 OH Estradiol Testosterone Female lion Male lion

Six functional groups are important in the chemistry of living things hydroxylcarbonylcarboxyl aminosulfhydrylphosphate

Hydoxyl Group formula structure – a H atom bonded to an O atom that is bonded to the carbon skeleton compounds – alcohols (names end in –ol) example H H H HH CC OH ethanol – in alcoholic beverages properties – polar, attracts H 2 O molecules, dissolves organic compounds

Carbonyl Group structure – a C joined to an O by a double bond compounds – ketones (if the carbonyl is in a carbon skeleton, non-terminal carbon) aldehydes (if the carbonyl is at the end of a carbon skeleton, terminal carbon) example acetone (simple ketone) H H H H H H C C C O CCC H H HH H O H propanol (an aldehyde) formula

Carboxyl Group structure – an O is double bonded to a C that is also bonded to an OH compounds – carboxylic acids formula example acetic acid (vinegar) H H C C H OH O properties – acidic properties

Amino Group structure – a N atom bonded to two H atoms and to the carbon skeleton compounds – amines example glycine O C HO C H H N H H properties – acts as a base, can pick up a proton from solution formula

Sulfhydryl Group structure – a S atom bonded to an atom of H compounds – thiols formula example ethanethiol HCC SH H H H H properties – can help stabilize protein structure by forming covalent bridges: disulfide bridges.

Phosphate Group structure – a P atom is bonded to four O atoms, one O atom is bonded to the carbon skeleton compounds – organic phosphates formula example glycerol phosphate H OH CCCOPOO OO HHH O H properties – makes molecule into an anion, transfers energy between organic molecules