Flashcards: Structure and Function of Large Biological Molecules
Macromolecules
A giant molecule formed by the joining of smaller molecules, usually by a dehydration reaction: a protein, carbohydrate, or nucleic acid. (these are all polymers) NOT LIPIDS
Polymer
long molecule consisting of many similar/identical monomers linked by covalent bonds (carbohydrates, proteins, and nucleic acids. NOT LIPIDS)
Monomer
A simple compound whose molecules can join together to form polymers
Enzymes
Catalysts for chemical reactions in living things. Increases rate of reaction w/ out being consumed by the reaction.
dehydration reaction (synthesis)
chemical reaction where two molecules become covalently bonded and lose a H2O molecule (monomer to polymer)
Hydrolysis
chemical reaction that breaks bonds between two molecules by the addition of an H2O molecule (polymer to monomer)
Carbohydrates
sugars and polymers of sugars
Monosaccharides
monomers of sugars (carbohydrates), simple sugars. Ex: glucose, fructose, galactose
disaccharides
Carbohydrates that are made up of two monosaccharides (sucrose, lactose, maltose)
Polysaccharides
Carbohydrates that are made up of more than two monosaccharides (storage for sugar, building material)
Starch
A storage polysaccharide in plants that stores glucose
Glycogen
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.
Cellulose
A substance (made of sugars) that is common in the cell walls of many organisms
Chitin
A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods (bugs)
Lipids
Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen and mix poorly with H2O (fats, phospholipids, steroids)
Fats
lipids consisting of 3 fatty acids linked to one glycerol molecule (store energy)
unsaturated fatty acids
A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail. (reduces number of H+) (ex: fish oil)
saturated fatty acid
all carbons connected by single bonds which maximizes the number of H+ (ex: butter)
trans fat
An unsaturated fat, formed artificially during hydrogenation of oils, containing one or more trans double bonds. (somewhat dangerous bc we can't always digest them?)
Phospholipids
A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail.
Steroids
lipids characterized by a carbon skeleton consisting of four fused rings (hydrophobic!) (some hormones)
Cholesterol
A lipid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids.
Protein
An organic compound that is made of one or more chains of amino acids and that is a principal component of all cells
peptide bond
covalent bond formed between amino acids, covalent, formed by dehydration synthesis
Polypeptide
long chain (polymer) of amino acids that makes proteins
amino acids
organic molecule w/ amino and carboxyl groups (monomers of polypeptides)
primary structure of protein
the sequence of amino acids (structure of proteins)
secondary structure of protein
The way in which the chain of amino acids of the polypeptides of a protein is folded. (structure of proteins)
tertiary structure of protein
Defined by the hydrophilic and hydrophobic interactions between R groups of amino acid chains. (structure of proteins)
quaternary structure of a protein
A number of polypeptide chains linked together, and sometimes associated with non-protein groups to form a protein. (two tertiary structures)
denaturation of proteins
proteins loses its shape due to chemical bond disruptions. (can take place with changes to pH, salt concentration, temperature, or exposure to toxic compounds)
Chaperonins
protein molecule complexes that assist with the proper folding of other proteins
nucelic acids
polymers consisting of many nucleotide monomers, blueprint for proteins (DNA and RNA)
Gene
A segment of DNA on a chromosome (specific nucleotide sequence) that codes for a specific trait
DNA (deoxyribonucleic acid)
A complex molecule containing the genetic information that makes up the chromosomes. (double stranded helix, Adenine, Cytosine, Guanine, Thymine are nitrogenous bases)
RNA (ribonucleic acid)
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
Messenger RNA (mRNA)
A type of RNA, synthesized from DNA and attached to ribosomes in the cytoplasm; (directs polypeptide production)
gene expression
The process by which information encoded in DNA directs the synthesis of proteins or, in some cases, RNAs that are not translated into proteins and instead function as RNAs.
Nucleotide
monomer of nucleic acids made up of a 5-carbon sugar, a phosphate group, and a nitrogenous base (building blocks of nucleic acids)
Pyridine
type of nitrogenous base w/ six membered ring (Cytosine, Thymine, Uracil)
Purine
type of nitrogenous base w/ six membered ring fused to a five membered ring (Adenine and Guanine) (use "Pure As Gold" to remember)
antiparallel
The opposite arrangement of the sugar-phosphate backbones in a DNA double helix. (5' to 3')