EXPERIMENT “Atmosphere”
CH4 Water vapor Electrode
Condenser
Cooled water containing Cold organic water molecules
H2O “sea”
Sample for chemical analysis 1 Molecular Structural Ball-and-Stick Space-Filling Name Formula Formula Model Model (a) Methane
(b) Ethane
(c) Ethene (ethylene)
2 Hydrogen Oxygen Nitrogen Carbon (valence = 1) (valence = 2) (valence = 3) (valence = 4)
H O N C
3 Urea
4 Ethane Propane 1-Butene 2-Butene (a) Length (c) Double bonds
Butane 2-Methylpropane (commonly called isobutane) Cyclohexane Benzene (b) Branching (d) Rings
5 Fat droplets (stained red)
100 µm (a) Mammalian adipose cells (b) A fat molecule
6 Pentane 2-methyl butane
(a) Structural isomers
cis isomer: The two Xs are trans isomer: The two Xs are on the same side. on opposite sides.
(b) Geometric isomers
L isomer D isomer (c) Enantiomers 7 Effective Ineffective Drug Condition Enantiomer Enantiomer
Ibuprofen Pain; inflammation S-Ibuprofen R-Ibuprofen
Albuterol Asthma
R-Albuterol S-Albuterol
8 L-dopa D-dopa
Testosterone
10 CHEMICAL Hydroxyl GROUP Carbonyl Carboxyl
STRUCTURE
(may be written HO—)
In a hydroxyl group (—OH), a The carbonyl group ( CO) When an oxygen atom is hydrogen atom is bonded to an consists of a carbon atom double-bonded to a carbon oxygen atom, which in turn is joined to an oxygen atom by a atom that is also bonded to bonded to the carbon skeleton of double bond. an —OH group, the entire the organic molecule. (Do not assembly of atoms is called confuse this functional group a carboxyl group (—COOH). with the hydroxide ion, OH–.)
NAME OF Alcohols (their specific names Ketones if the carbonyl group is Carboxylic acids, or organic COMPOUND usually end in -ol) within a carbon skeleton acids Aldehydes if the carbonyl group is at the end of the carbon skeleton
EXAMPLE
Ethanol, the alcohol present in Acetone, the simplest ketone Acetic acid, which gives vinegar alcoholic beverages its sour taste
Propanal, an aldehyde
FUNCTIONAL Is polar as a result of the A ketone and an aldehyde may Has acidic properties PROPERTIES electrons spending more time be structural isomers with because the covalent bond near the electronegative different properties, as is the between oxygen and hydrogen oxygen atom. case for acetone and propanal. is so polar; for example, Can form hydrogen bonds with These two groups are also water molecules, helping found in sugars, giving rise to dissolve organic compounds two major groups of sugars: such as sugars. aldoses (containing an aldehyde) and ketoses (containing a ketone). Acetic acid Acetate ion
Found in cells in the ionized form with a charge of 1– and called a carboxylate ion (here, specifically, the acetate ion).
11 CHEMICAL Amino Sulfhydryl Phosphate Methyl GROUP
(may be STRUCTURE written HS—)
The amino group The sulfhydryl group In a phosphate group, a A methyl group consists of a (—NH2) consists of a consists of a sulfur atom phosphorus atom is bonded to carbon bonded to three nitrogen atom bonded bonded to an atom of four oxygen atoms; one oxygen hydrogen atoms. The methyl to two hydrogen atoms hydrogen; resembles a is bonded to the carbon skeleton; group may be attached to a and to the carbon hydroxyl group in shape. two oxygens carry negative carbon or to a different atom. skeleton. charges. The phosphate group 2– (—OPO3 , abbreviated P ) is an ionized form of a phosphoric acid 2 group (—OPO3H ; note the two hydrogens).
NAME OF Amines Thiols Organic phosphates Methylated compounds COMPOUND
EXAMPLE
Glycine Glycerol phosphate Cysteine Because it also has a In addition to taking part in carboxyl group, glycine many important chemical 5-Methyl cytidine is both an amine and Cysteine is an important reactions in cells, glycerol a carboxylic acid; sulfur-containing amino 5-Methyl cytidine is a compounds with both phosphate provides the acid. backbone for phospholipids, component of DNA that has groups are called been modified by addition of amino acids. the most prevalent molecules in cell membranes. the methyl group.
FUNCTIONAL Acts as a base; can Two sulfhydryl groups Contributes negative charge Addition of a methyl group PROPERTIES pick up an H+ from can react, forming a to the molecule of which it is to DNA, or to molecules the surrounding covalent bond. This a part (2– when at the end of bound to DNA, affects solution (water, in “cross-linking” helps a molecule; 1– when located expression of genes. living organisms). stabilize protein internally in a chain of structure. phosphates). Arrangement of methyl groups in male and female Cross-linking of Has the potential to react sex hormones affects cysteines in hair with water, releasing energy. their shape and function. proteins maintains the curliness or straightness (nonionized) (ionized) of hair. Straight hair can be “permanently” curled Ionized, with a by shaping it around charge of 1+, under curlers, then breaking cellular conditions. and re-forming the cross-linking bonds.
12 Reacts with H2O
P P P Adenosine P i P P Adenosine Energy ATP Inorganic ADP phosphate
13