The Chemistry of Life: Organic Compounds
Carbon is the backbone of large, complex molecules. Carbon to carbon bonds are strong and not easily broken.
Hydrocarbons are organic compounds consisting of carbon and hydrogen. Hydrocarbons are insoluble in water and combine together through hydrophobic interactions.
Isomers are compounds with the same molecular formulas but different structures and different properties.
Structural isomers are compounds that are different in the covalent arrangement of their atoms.
Geometric isomers have identical covalent bonds but differ in the order in which they are arranged.
Enantiomers are mirror images of each other.
A functional group is a group of atoms that determine the type of chemical reaction.
The methyl group is nonpolar and is abbreviated R - CH3.
The hydroxyl group is polar and is abbreviated R - OH.
The carbonyl group is polar and there are two types of carbonyl groups: an aldehyde and a ketone.
An aldehyde is abbreviated R - CHO.
A ketone is abbreviated R - CO - R.
The carboxyl group is polar, weakly acidic, can release an H+, and is abbreviated R - COOH.
An amino group is weakly basic, can accept an H+, and is abbreviated R - NH2.
A phosphate group is weakly acidic and is abbreviated R - PO4H2.
The sulfhydryl group helps stabilize proteins and is abbreviated R - SH.
Macromolecules are large molecules.
Polymers are created by linking small molecules called monomers.
Polymers can be degraded to monomers by hydrolysis reactions.
Monomers are linked by condensation reactions.
Carbohydrates are sugars, starches, and cellulose. Primarily consists of carbon, hydrogen, and oxygen. Primary function: cell fuel and energy storage.
Monosaccharides are simple sugars. Examples: glucose and fructose.
Glucose is the most abundant monosaccharide and is used as a source of energy in many organisms.
A disaccharide consists of two monosaccharides linked by a glycosidic linkage. Examples: maltose and sucrose
A polysaccharide is a macromolecule containing repeating units of monosaccharides. Examples of polysaccharides include cellulose, starches, and glycogen.
Carbohydrates can combine with proteins to form glycoproteins and lipids to form glycolipids.
Lipids are nonpolar and insoluble in water. Primarily consists of carbon, hydrogen, and oxygen (sometimes nitrogen, and phosphorus). Primary function: energy storage, thermal insulation.
The most abundant lipid is triacylglycerols. Triacylglycerols are formed from glycerol and three fatty acids.
Glycerol is a 3- carbon alcohol that has three hydroxyl groups
A fatty acid a long hydrocarbon chain with a carboxyl group
Phospholipids are amphipathic, meaning they contain a hydrophilic head and hydrophobic tails.
Proteins are composed of amino acids. Primarily consists of carbon, hydrogen, oxygen, and nitrogen.
Peptide bonds join amino acids.
Enzymes are molecules that speed up chemical reactions.
Structural proteins strengthen and protect cells and tissues.
Transport proteins move substances between cells and across cell membranes.
Storage proteins store nutrients.
Regulatory proteins control the activities of proteins, genes, and cells.
Motile proteins generate movement in cells and tissues.
Protective proteins defend against foreign invaders.
Proteins have four levels of organization: primary, secondary, tertiary, and quaternary.
Primary structure is the amino acid sequence.
Secondary structure is the result of hydrogen bonding involving the backbone.
Tertiary structure is the overall shape of each individual polypeptide chain.
Quaternary structure is the resulting 3-D structure.
Nucleic acids are macromolecules that transmit hereditary information. Primarily consists of carbon, hydrogen, oxygen, nitrogen, and phosphorus.
There are two types of nucleic acids: deoxyribonucleic acid and ribonucleic acid.
Deoxyribonucleic acid (DNA) makes up the hereditary material of the cell.
Ribonucleic acid (RNA) is involved in the process of converting amino acids to polypeptides to proteins.
Nucleic acids are polymers of nucleotides.
Nucleotides consist of a 5 carbon sugar, DNA or RNA, a phosphate group, and a nitrogenous base (adenine, thymine, guanine, and cytosine).
Purines are double-ringed and are adenine and guanine.
Pyrimidines are single-ringed and are cytosine and thymine.
Nucleotides are joined together by phosphodiester linkages.
Adenosine triphosphate (ATP) is composed of adenine, ribose, and three phosphates and is the primary energy currency of cells.