Unit 3 Carbon

Isomer

One of two or more compounds that have the same number of atoms of the same elements but different structures and hence different properties.

Sicklecell disease

A recessively inherited human blood disorder in which a single nucleotide change in the Beta

Unsaturated fatty acid

A fatty acid that has one or more double bonds between carbons in the hydrocarbon tail. Such bonding reduces the number of hydrogen atoms attached to the carbon skeleton.

Steroid

A type of lipid characterized by a carbon skeleton consisting of four fused rings with various chemical groups attached.

Cholesterol

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 many hormones.

Organic compound

A chemical compound containing carbon.

polysaccharide

A polymer of many monosaccharides, formed by dehydration reactions.

Polynucleotide

A polymer consisting of many nucleotide monomers in a chain. The nucleotides can be those of DNA or RNA.

a helix

A coiled region constituting one form of the secondary structure of proteins, arising from a specific pattern of hydrogen bonding between atoms of the polypeptide backbone (not side chains).

Glycogen

An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.

Macromolecule

a giant molecule formed by the joining of smaller molecules, usually by a dehydration reaction. Polysaccharides, proteins, and nucleic acids are macromolecules

Hydrocarbons

Compounds composed of only carbon and hydrogen, lipids of long tails of these, always hydrophobic and can release large amount of energy

Functional groups

A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and involved in chemical reactions

Beta pleated sheet

One form of the secondary structure of proteins in which the polypeptide chain folds back and forth. Two regions of the chain lie parallel to each other and are held together by hydrogen bonds between atoms of the polypeptide backbones (not the side chains).

Quaternary structure

The particular shape of a complex, aggregate protein, defined by the characteristic three

Valence

The bonding capacity of a given atom; the number of covalent bonds an atom can form, which usually equals the number of unpaired electrons in its outermost (valence) shell.

Peptide bond

The covalent bond between the carboxy group on one amino acid and the amino group on another, formed by a dehydration reaction.

Chitin

A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeleton of all arthropods.

Disaccharide

A double sugar, consisting of two monosaccharides joined by a glycosidic linkage formed by a dehydration reaction.

Ribose

The sugar component of RNA nucleotides.

Monosaccharide

The simplest carbohydrate, acting alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, monosaccharides have molecular formulas that are generally some multiple of CH2O.

Hydrophobic interaction

A type of weak chemical interaction caused when molecules that do not mix with water coalesce to exclude water.

Triacylglycerol

A lipid consisting of three fatty acids linked to one glycerol molecule; also called a triacylglycerol or triglyceride.

Double helix

The form of native DNA, referring to its two adjacent antiparallel polynucleotide strands wound around an imaginary axis into a spiral shape.

Primary structure

The level of protein structure referring to the specific linear sequence or amino acids.

Polymer

A long molecule consisting of many similar or identical monomers linked together by covalent bonds.

Nucleic acid

A polymer (polynucleotide) consisting of many nucleotide monomers; serves as a blueprint for proteins and, through the actions of proteins, for all cellular activities. The two types are DNA and RNA.

Polypeptide

A polymer of many amino acids linked together by peptide bonds.

Hydrolysis

A chemical reaction that breaks bonds between two molecules by the addition of water; functions in disassembly of polymers to monomers.

Hydrocarbon

An organic molecule consisting of only carbon and hydrogen.

Evolutionary lineage

The sequence of ancestral organisms leading to a particular taxon; represented by a branch (line) in a phylogenetic tree.

Protein

A biologically functional molecule consisting of one or more polypeptides folded and coiled into a specific three

Antiparallel

Referring to the arrangement of the sugar

Deoxyribonucleic acid (DNA)

A nucleic acid molecule, usually a double

Pyrimidine

One of two types of nitrogenous bases found in nucleotides, characterized by a six

Amino acid

An organic molecule possessing both a carboxyl and an amino group. Amino acids serve as the monomers of polypeptides.

Trans fat

An unsaturated fat, formed artificially during hydrogenation of oils, containing one or more trans double bonds.

Nucleotide

The building block of a nucleic acid, consisting of a five

Dehydration reaction

A chemical reaction in which two molecules become covalently bonded to each other with the removal of a water molecule.

Tertiary structure

The overall shape of a protein molecule due to interactions of amino acid side chains, including hydrophobic interactions, ionic bonds, hydrogen bonds, and disulfide bridges.

Bioinformatics

The use of computers, software, and mathematical information from large data sets.

Structural Isomer

One of two or more compounds that have the same molecular formula but differ in the covalent arrangements of their atoms.

Lipid

Any of a group of large biological molecules, including fats, phospholipids, and steroids, that mix poorly, if at all, with water.

Phospholipid

A lipid that is made of glycerol joined to two fatty acids and a phosphate group. The hydrocarbon chains of the fatty acids act a nonpolar, hydrophobic tails, while the rest of the molecule act as polar, hydrophilic heads. Phospholipids form bilayers that function as biological membranes.

Secondary structures

Regions of repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bonding between constituents of the backbone (not the side chains).

Saturated fatty acid

A fatty acid in which all carbons in the hydrocarbon tail are connected by a single bonds, thus maximizing the number of hydrogen atoms attached to the carbon skeleton.

Cellulose

A structural polysaccharide of plant cell walls, consisting of glucose monomers joined by beta glycosidic linkages.

Denaturation

in proteins, a process in which a protein loses its native shape due to the disruption if weak chemical bonds and interactions, thereby becoming biologically inactive; in DNA, the separation of the two strands of the double helix. Denaturation occurs under extreme (noncellular) conditions of pH, salt concentration, or temperature.

Proteomics

The systematic study of the full protein sets (proteomes) encoded by genomes.

Disulfide bridges

A strong covalent bond formed when the sulfur of one cysteine monomer bonds to the sulfur of another cysteine monomer.

Purine

One of two types of nitrogenous bases found in nucleotides, characterized by a six

Monomer

The subunit that serves as the building block of a polymer.

Glycosidic linkage

A covalent bond formed between two monosaccharides by a dehydration reaction.

X

ray crystallography

Genomics

The study of whole sets of genes and their interactions within a species, as well as genome comparisons between species.

Gene

A discrete unit of hereditary information consisting a specific nucleotide sequence in DNA (or RNA, in some viruses).

Catalyst

A chemical agent that selectively increases the rate of a reaction without being consumed by the reaction,

Adenosine trisphosphate

See ATP (adenosine triphosphate).

Cis

trans isomer

Enantiomer

One of two compounds that are mirror images of each other and that differ in shape due to the presence of an asymmetric carbon.

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.

Ribonucleic acid (RNA)

A type of nucleic acid consisting of a polynucleotide made up of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine C guanine (G), and uracil (U); usually single

Enzyme

A macromolecule serving as a catalyst, a chemical agent that increases the rate of interactions without being consumed by the reactions. Most enzymes are proteins.

Deoxyribose

The sugar component of DNA nucleotides, having one fewer hydroxyl group than ribose, the sugar component of RNA nucleotides.

Starch

A storage polysaccharide in plants, consisting entirely of glucose monomers joined by glycosidic linkages.

Fatty acid

A carboxylic acid with a long carbon chain. Fatty acids vary in length and in the number and location of double bonds; three fatty acids linked to a glycerol molecule form a fat molecule, also known as a triacylglycerol or triglyceride.