Chapter 5 Flashcards
A giant molecule formed by the joining of smaller molecules, usually by a condensation reaction.
Macromolecule
A long molecule consisting of many similar or identical monomers linked together.
Polymer
The subunit that serves as the building block of a polymer.
Monomer
A reaction in which two molecules become covalently bonded to each other through the loss of a small molecule, usually water, in which case it is also called a dehydration reaction.
Condensation Reaction
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule.
Dehydration Synthesis (Reaction)
A macromolecule serving as a catalyst, a chemical agent that changes the rate of a reaction without being consumed by the reaction.
Enzymes
A chemical process that lyses, or splits, molecules by the addition of water, functioning in disassembly of polymers to monomers.
Hydrolysis
A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides).
Carbohydrates
The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides.
Monosaccharides
A double sugar, consisting of two monosaccharides joined by a glycosidic linkage formed during dehydration synthesis.
Disaccharide
A covalent bond formed between two monosaccharides by a dehydration reaction.
Glycosidic Linkage
A polymer of many monosaccharides, formed by dehydration reactions.
Polysaccharide
A storage polysaccharide in plants, consisting entirely of glucose monomers joined by glycosidic linkages.
Starch
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of a starch.
Glycogen
A structural polysaccharide of plant cell walls, consisting of glucose monomers joined by ß glycosidic linkages.
Cellulose
One of a group of compounds, including fats, phospholipids, and steroids, that mix poorly, if at all, with water.
Lipids
A lipid consisting of three fatty acids linked to one glycerol molecule; also called a triacylglycerol or triglyceride.
Fat
A long carbon chain carboxylic acid.
Fatty Acid
A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that are attached to the carbon skeleton.
Saturated Fatty Acid
A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail.
Unsaturated Fatty Acid
An unsaturated fat containing one or more trans double bonds.
Trans Fat
A lipid made up of glycerol joined to two fatty acids and a phosphate group.
Phospholipids
A type of lipid characterized by a carbon skeleton consisting of four rings with various chemical groups attached.
Steroid
A steroid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids, such as hormones.
Cholesterol
A chemical agent that increases the rate of a reaction without being consumed by the reaction.
Catalyst
A polymer (chain) of many amino acids linked together by peptide bonds.
Polypeptide
A functional biological molecule consisting of one or more polypeptides folded and coiled into a specific three-dimensional structure.
Protein
An organic molecule possessing both carboxyl and amino groups. Amino acids serve as the monomers of polypeptides.
Amino Acid
The covalent bond between the carboxyl group on one amino acid and the amino group on another, formed by a dehydration reaction.
Peptide Bond
The level of protein structure referring to the specific sequence of amino acids.
Primary Structure (of a protein)
The localized, repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bond formation between constituents of the backbone.
Secondary Structure (of a protein)
Irregular contortions of a protein molecule due to interactions of side chains involved in hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.
Tertiary Structure (of a protein)
A strong covalent bond formed when the sulfur of one cysteine monomer bonds to the sulfur of another cysteine monomer.
Disulfide Bridges
The particular shape of a complex, aggregate protein, defined by the characteristic three-dimensional arrangement of its constituent subunits, each a polypeptide.
Quaternary Structure (of a protein)
In proteins, a process in which a protein unravels and loses its native shape, thereby becoming biologically inactive; in DNA, the separation of the two strands of the double helix.
Denaturation
A protein molecule that assists in the proper folding of other proteins.
Chaperonins
A technique that depends on the diffraction of an X-ray beam by the individual atoms of a crystallized molecule to study the three-dimensional structure of the molecule.
X-ray Crystallography
A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).
Gene
A polymer (polynucleotide) consisting of many nucleotide monomers; serves as a blueprint for proteins and, through the actions of proteins, for all cellular activities.
Nucleic Acid
A double-stranted, helical nucleic acid molecule, consisting of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine, cytosine, guanine, and thymine; capable of being replicated and determining the inherited structure of a cell’s proteins.
DNA
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine, cytosine, guanine, and uracil; usually single-stranded; functions in protein synthesis, gene regulation, and as the genome of some viruses.
RNA
One of two types of nitrogenous bases found in nucleotides, characterized by a sin-membered ring. Cytosine, thymine, and uracil are these.
Pyrimidine
One of two types of nitrogenous bases found in nucleotides, characterized by a six-membered ring fused to a five-membered ring. Adenine and guanine are these.
Purine
The form of native DNA, referring to its two adjacent antiparallel polynucleotide strands wound around an imaginary axis into a spiral shape.
Double Helix
