Chapter 3 VOCAB

organic compounds

carbon-based molecules. usually contains hydrogen atoms in addition


compounds with the same molecular formula but different structural arrangements


molecules that only contain carbon and hydrogen

functional groups

hydroxyl, carbonyl, carboxyl, amino, and phosphate group. They affect the molecule's function by participating in chemical reactions. All are polar, which tends to make compounds containing them hydrophilic.



hydroxyl group

Hydrogen atom bonded to an oxygen atom (OH), and the oxygen is connected to the carbon skeleton. Organic compounds that contains this group is called alcohol.

carbonyl group

A carbon atom is linked by a double bond to an oxygen atom (C=O). If this group is at the end of a carbon skeleton, the compound is called an aldehyde. If this group is within a chain of a carbon skeleton, the compound is called a ketone.

carboxyl group

A carbon double-bonded to an oxygen atom and also bonded to a hydroxyl group. Releases the hydrogen, becoming ionized and makes the compound acidic.

amino group

A nitrogen is bonded to 2 hydrogens and the carbon skeleton. Takes a hydrogen, becoming ionized and makes the compound basic.

phosphate group

A phosphorus atom bonded to 4 oxygen atoms. Double bonded to one of the oxygens.

methyl group

carbon bonded to 3 hydrogen atoms


gigantic molecules by making polymers out of monomers.


a long molecule consisting of many identical or similar building blocks strung together


the building blocks of polymers

dehydration reaction

a reaction that removes a molecule of water as 2 molecules become bonded together


the digestion process when water is used to break down polymers into monomers


specialized macromolecules that speed up chemical reactions in cells


molecules that range from small sugar molecules to starch molecules


monomers of carbohydrates


a common monosaccharide of central importance in the chemistry of life. C6H12O6


2 monosaccharide monomers form by a dehydration reaction


macromolecules. polymers of hundreds to thousands of monosaccharides linked together by dehydration reactions


a storage polysaccharide in plants, and consists of long chains of glucose monomers


a polysaccharide animals store glucose in


the most abundant organic compound on Earth, and a major component of the tough walls that enclose plant cells. This is not a nutrient for humans


a structural polysaccharide used by insects and crustaceans to build their exoskeleton


a diverse group of molecules that are classified together because they all do not mix well with water.lipids include fats, phospholipids, and steroids




a large lipid made from 2 kinds of smaller molecules: glycerol & fatty acids

unsaturated fatty acid

a fatty acid whose hydrocarbon chain contains one or more double bonds

saturated fatty acid

a fatty acid that has no double bonds in its hydrocarbon chain has the maximum number of hydrogen atoms attached to each carbon atom

trans fat

an unsaturated fat that was turned into a saturated fat by hydrogenation (adding hydrogen) which associates with health risks


lipid that is the major component of cell membrane


lipids in which the carbon skeleton contains 4 fused rings


a common component in animal cell membranes and is also the precursor for making other steroids, including sex hormones. lipid


a polymer of small building blocks called amino acids.


the process when a protein unravels, losing its shape and function

amino acids

have a carboxyl group, amino group, hydrogen, and R group all covalently bonded by a carbon

peptide bond

a covalent bond between 2 amino acids after dehydration synthesis. creates a dipeptide or a polypeptide


a chain of amino acids formed by dehydration reaction and bonded by peptide bonds.

primary structure

the precise sequence of amino acids in the polypeptide chain in a protein

secondary structure

segments of the primary structure then coiled or folded into local patterns in a protein

tertiary structure

the overall 3D shape of a protein

quaternary structure

proteins with more than 1 polypeptide chain