Chapter 3 Organic Molecules/Macromolecules Flashcards
Hydrocarbon
An organic compound composed solely of hydrogen
and carbon atoms.
Isomers
One of two or more chemical compounds having the same chemical formula but diff erent structural formulas
Structural Isomers
One of two or more chemical compounds having
the same chemical formula but diff ering in the covalent arrangement of their atoms, e.g., glucose and fructose.
Geometric Isomers
One of two or more chemical compounds having
the same arrangement of covalent bonds but differing in the spatial arrangement of their atoms or groups of atoms.
Hydrophobic
Not readily interacting with water; having less affinity
for water molecules than they have for each other.
Hydrophilic
Interacting readily with water; having a greater affinity
for water molecules than they have for each other.
Functional groups
A group of atoms that confers distinctive properties
on an organic molecule (or region of a molecule) to which it is attached, e.g., hydroxyl, carbonyl, carboxyl, amino, phosphate, sulfhydryl groups.
Methyl group
A nonpolar functional group; abbreviated ¬CH3.
Hydroxyl group
Polar functional group; abbreviated
¬OH.
Carbonyl group
A polar functional group consisting of a carbon
attached to an oxygen by a double bond; found in aldehydes and ketones.
Aldehyde
An organic molecule containing a carbonyl group bonded to at least one hydrogen atom
Ketone
An organic molecule containing a carbonyl group bonded to two carbon atoms
Amino group
A weakly basic functional group; abbreviated ¬NH2.
Phosphate group
A weakly acidic functional group that can release
one or two hydrogen ions
Sulfhydryl group
Functional group abbreviated ¬SH; found in
organic compounds called thiols.
Macromolecules
A very large organic molecule, such as a protein or
nucleic acid. Typically composed of thousands of molecule chains
Polymers
A molecule built up from repeating subunits of the same general type (monomers); examples include proteins, nucleic acids, or polysaccharides.
Monomers
A molecule that can link with other similar molecules; two monomers join to form a dimer, whereas many form a polymer. Monomers are small or large
Hydrolysis reaction
Reaction in which a covalent bond between two subunits is broken through the addition of the equivalent of a water molecule; a hydrogen atom is added to one subunit and a hydroxyl group to the other.
Condensation reaction
A reaction in which two monomers are combined covalently through the removal of the equivalent of a water molecule.
Carbohydrates
Compound containing carbon, hydrogen, and oxygen,
in the approximate ratio of C:2H:O, e.g., sugars, starch, and cellulose.
Monosaccharides
A sugar that cannot be degraded by hydrolysis to a simpler sugar
Disaccharides
A sugar produced by covalently linking two monosaccharides
Glucose
(C6H12O6), A hexose aldehyde sugar that is central to many metabolic processes.
Glycosidic linkage
Covalent linkage joining two sugars; includes an
oxygen atom bonded to a carbon of each sugar..
Polysaccharides
A carbohydrate consisting of many monosaccharide subunits
Starch
- The typical form of carbohydrate used for energy storage in plants, is a polymer consisting of a-glucose subunits.
- composed of alpha glucose subunits; made
by plants for energy storage.
Amyloplasts
Colorless plastids; include amyloplasts, which are used
for starch storage in cells of roots and tubers.
Glycogen
(animal starch)The principal storage polysaccharide in
animal cells; formed from glucose and stored primarily in the liver and, to a lesser extent, in muscle cells.
Cellulose
A structural polysaccharide consisting of beta glucose subunits; the main constituent of plant primary cell walls.
Chitin
A nitrogen-containing structural polysaccharide that
forms the exoskeleton of insects and the cell walls of many fungi.
Glycoproteins
A protein with covalently attached carbohydrates compounds present on the outer surface of cells other than bacteria.
Lipids
- Lipids are a group of naturally occurring molecules that include fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, phospholipids, and others.
- Any of a group of organic compounds that are insoluble in water but soluble in nonpolar solvents; lipids serve as energy storage
and are important components of cell membranes.
Triacylglycerols
The main storage lipid of organisms, consisting of a glycerol combined chemically with three fatty acids; also called triglyceride.
Glycerol
A three-carbon alcohol with a hydroxyl group on each
carbon; a component of triacylglycerols and phospholipids, as well as monoacylglycerols and diacylglycerols.
Fatty acid
A lipid that is an organic acid containing a long hydrocarbon chain component of triacylglycerols and phospholipids, as well as monoacylglycerols and diacylglycerols.
Ester linkage
Covalent linkage formed by the reaction of a carboxyl
group and a hydroxyl group, with the removal of the equivalent of a water molecule; the linkage includes an oxygen atom bonded to a carbonyl group
Monoglyceride
Lipid consisting of glycerol combined chemically with a single fatty acid
Diglyceride
A lipid consisting of glycerol combined chemically with two fatt y acids; also called diglyceride.
Saturated fatty acids
with no double bonds
Unsaturated fatty acids
one doublebond
Monounsaturated fatty acids
one double
bond
Polyunsaturated fatty acids
two or more double bonds
Amphipathic
A molecule containing both hydrophobic and hydrophilic regions.
Phospholipids
Consists of a glycerol molecule attached at one end to two fatty acids and at the other end to a phosphate group linked to an organic compound such as choline. The organic compound usually contains nitrogen.
Carotenoids
Carotenoids are organic pigments that are found in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms.
Isophrene units
many important pigments consist of five-carbon hydrocarbon
monomers
Steroid
consists of carbon atoms arranged in four attached rings; three of the rings contain six carbon atoms, and the fourth contains five
Protein
Macromolecules composed of amino acids, are the most versatile cell components.
Enzymes
molecules that accelerate the thousands of different chemical reactions that take place in an organism; are proteins.
Aminoacids
- The constituents of proteins, have an amino group(-NH2) and a carboxyl group (-COOH) bonded to the same asymmetrical carbon atom, known as the alpha carbon.
- Twenty amino acids are commonly found in proteins, each identified by the variable side chain (R group) bonded to the a carbon
Alpha carbons
The alpha carbon (α carbon) in organic molecules refers to the first carbon atom that attaches to a functional group, such as a carbonyl.
Beta carbons
The carbon atom one removed from an atom, group, functional group, or other moiety of interest.
Essential amino acids
Those an animal cannot synthesize in amounts suffi cient to meet its needs and must obtain from the diet.
Peptide bond
The covalent carbon to nitrogen
bond linking two amino acids
Dipeptide
When two amino acids combine.
Polypeptide
Polypeptides are chains of amino acids. Proteins are made up of one or more polypeptide molecules.
Globular proteins
Proteins tightly folded into compact, roughly spherical shapes.
Primary structure
The primary structure of a peptide or protein is the linear sequence of its amino acid structural units, and partly comprises its overall biomolecular structure. By convention, the primary structure of a protein is reported starting from the amino-terminal (N) end to the carboxyl-terminal (C) end.
Secondary structure
The general three-dimensional form of local segments of proteins. Secondary structure can be formally defined by the pattern of hydrogen bonds of the protein (such as alpha helices and beta sheets) that are observed in an atomic-resolution structure.
Alpha helix
a region where a polypeptide chain forms a uniform helical coil.
Beta pleated sheet
The β sheet (also β-pleated sheet) is the second form of regular secondary structure in proteins. Beta sheets consist of beta strands connected laterally by at least two or three backbone hydrogen bonds, forming a generally twisted, pleated sheet.
Tertiary structure
The term protein tertiary structure refers to a protein’s geometric shape. The tertiary structure will have a single polypeptide chain “backbone” with one or more protein secondary structures, the protein domains.
Quartiary structure
In biochemistry, quaternary structure is the number and arrangement of multiple folded protein subunits in a multi-subunit complex. It includes organisations from simple dimers to large homooligomers and complexes with defined or variable numbers of subunits.
Molecular chaperones
Molecular chaperones are proteins that assist the covalent folding or unfolding and the assembly or disassembly of other macromolecular structures.
Domain
A single protein may have more than one distinct structural region called a domain.
Nucleic acids
Nucleic acids are biopolymers, or large biomolecules, essential for all known forms of life. Nucleic acids, which include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid), are made from monomers known as nucleotides.
DNA
Deoxyribonucleic acid is a molecule that carries most of the genetic instructions used in the development, functioning and reproduction of all known living organisms and many viruses. DNA is a nucleic acid; alongside proteins and carbohydrates, nucleic acids compose the three major macromolecules essential for all known forms of life.
RNA
Ribonucleic acid (RNA) is a polymeric molecule implicated in various biological roles in coding, decoding, regulation, and expression of genes.
Ribosomes
The ribosome is a large and complex molecular machine, found within all living cells, that serves as the site of biological protein synthesis. Ribosomes link amino acids together in the order specified by messenger RNA (mRNA) molecules.
Nucleotides
Nucleotides are organic molecules that serve as the monomers, or subunits, of nucleic acids like DNA and RNA. The building blocks of nucleic acids, nucleotides are composed of a nitrogenous base, a five-carbon sugar (ribose or deoxyribose), and at least one phosphate group.
Deoxyribose
Deoxyribose, or more precisely 2-deoxyribose, is a monosaccharide with idealized formula H−(C=O)−(CH2)−(CHOH)3−H. Its name indicates that it is a deoxy sugar, meaning that it is derived from the sugar ribose by loss of an oxygen atom.
Ribose
Ribose is an organic compound with the formula C5H10O5; specifically, a pentose monosaccharide (simple sugar) with linear form H−(C=O)−(CHOH)4−H, which has all the hydroxyl groups on the same side in the Fischer projection.
Purine
A purine is a heterocyclic aromatic organic compound. It consists of a pyrimidine ring fused to an imidazole ring. Purines and pyrimidines make up the two groups of nitrogenous bases, including the two groups of nucleotide bases.
Pyrimidine
Pyrimidine is one of two classes of heterocyclic nitrogenous bases found in the nucleic acids DNA and RNA: in DNA the pyrimidines are cytosine and thymine, in RNA uracil replaces thymine.
Adenine
Adenine is a nucleobase (a purine derivative) with a variety of roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD) and flavin adenine dinucleotide (FAD).
Guanine
Is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine (uracil in RNA).
Cytocine
Cytosine is one of the four main bases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA).
Thymine
Is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine.
Uracil
Is one of the four nucleobases in the nucleic acid of RNA that are represented by the letters A, G, C and U. The others are adenine (A), cytosine (C), and guanine (G). In RNA, uracil binds to adenine via two hydrogen bonds. In DNA, the uracil nucleobase is replaced by thymine. Uracil could be considered a demethylated form of thymine.
Phosphodiester linkage
A phosphodiester bond occurs when exactly two of the hydroxyl groups in phosphoric acid react with hydroxyl groups on other molecules to form two ester bonds.
Adenosine triphosphate
Adenosine triphosphate (ATP) is a nucleoside triphosphate used in cells as a coenzyme often called the “molecular unit of currency” of intracellular energy transfer.
Guanosine triphosphate
Is a purine nucleoside triphosphate. It can act as a substrate for the synthesis of RNA during the transcription process or DNA during DNA replication.
Cyclic adenosine monophosphate
Cyclic adenosine monophosphate (cAMP, cyclic AMP, or 3’,5’-cyclic adenosine monophosphate) is a second messenger important in many biological processes. cAMP is derived from adenosine triphosphate (ATP) and used for intracellular signal transduction in many different organisms, conveying the cAMP-dependent pathway.
Cyclic guanosine monophosphate
Cyclic guanosine monophosphate (cGMP) is a cyclic nucleotide derived from guanosine triphosphate (GTP). cGMP acts as a second messenger much like cyclic AMP.
Nicotinamide adenine dinucleotide
Nicotinamide adenine dinucleotide (NAD) is a coenzyme found in all living cells. The compound is a dinucleotide, because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine base and the other nicotinamide. Nicotinamide adenine dinucleotide exists in two forms, an oxidized and reduced form abbreviated as NAD+ and NADH respectively.
Enantiomers
Isomers that are mirror images of each other.
Carboxyl
(abbreviated ROCOOH) in its nonionized form consists of a carbon atom joined by a double covalent bond to an oxygen atom, and by a single covalent bond to another oxygen, which is in turn bonded to a hydrogen atom.
