BIO - TERMS - ACID Flashcards
acid dissociation constant
The dissociation constant (Ka) of an acid, describing its dissociation into its conjugate base and a proton.
acid ionization constant (Ka)
The equilibrium constant for the ionization reaction of a weak acid; used to compare the relative strengths of weak acids.
acid-fast stain
A differential stain used to identify bacteria that are not decolorized by acid-alcohol.
acid–base reaction (neutralization reaction)
A reaction in which an acid reacts with a base and the two neutralize each other, producing water.
acid–base titration
A laboratory procedure in which a basic (or acidic) solution of unknown concentration reacts with an acidic (or basic) solution of known concentration in order to determine the concentration of the unknown.
acidic solution
A solution containing an acid that creates additional H3O+ ions, causing 3H3O+4 to increase.
algin
A sodium salt of mannuronic acid (C6H8O6); found in brown algae.
ampholyte
A substance that can act as either a base or an acid.
anaplerotic reaction
An enzyme-catalyzed reaction that can replenish the supply of intermediates in the citric acid cycle.
Anaplerotic reactions
Reactions that result in the net production of a tricarboxylic acid (TCA) cycle intermediate.
Annealing
Formation of a double strand from two complementary nucleic acid strands.
Antioxidant defense
The whole biochemical system of the cell that decomposes reactive oxygen and reactive nitrogen species. It consists of enzymes including superoxide dismutase and peroxidases and low molecular mass molecules such as ascorbic acid and glutathione.
Arrhenius definitions (of acids and bases)
According to these definitions, an acid is defined as a substance that produces H+ ions in aqueous solution, and a base is defined as a substance that produces OH- ions in aqueous solution.
Arsenite
An inhibitor of pyruvate dehydrogenase that binds to dihydrolipoic acid.
autoionization
The process by which water acts as an acid and a base with itself.
Base analogs
Unnatural purine or pyrimidine bases that differ slightly from the normal bases and that can be incorporated into nucleic acids. They are often mutagenic.
Base stacking
The noncovalent interaction between successive bases within a nucleic acid strand.
bi-orientation
The attachment of sister chromatids to opposite poles of the mitotic spindle, so that they move to opposite ends of the cell when they separate in anaphase. binding site Region on the surface of one molecule (usually a protein or nucleic acid) that can interact with another molecule through noncovalent bonding.
binary acid
An acid composed of hydrogen and a nonmetal.
Brønsted–Lowry base
A substance that accepts H1 from an acid.
Brønsted–Lowry definitions (of acids and bases)
According to these definitions, an acid is defined as a proton (H+ ion) donor and a base is defined as a proton acceptor.
buffer capacity
The amount of acid or base that can be added to a buffer without causing a large change in pH.
C6-C1-phenolics
Heterogenous collection of simple phenolic compounds derived from intermediates of the shikimate pathway. Examples include gallic acid and salicylic acid.
Cannizzaro reaction
The disproportionation reaction of an aldehyde on treatment with base to yield an alcohol and a carboxylic acid.
Carboxylic acid derivative
A compound in which an acyl group is bonded to an electronegative atom or substituent that can act as a leaving group in a substitution reaction. Esters, amides, and acid halides are examples.
CD22
An inhibitory receptor on B cells that binds sialic acid-modified glycoproteins commonly found on mammalian cells and contains an ITIM motif in its cytoplasmic tail.
CD44
Also known as phagocytic glycoprotein-1 (Pgp1), CD44 is a cellsurface glycoprotein expressed by naive lymphocytes and upregulated on activated T cells. It is a receptor for hyaluronic acid and functions in cell–cell and cell–extracellular matrix adhesion. High expression of CD44 is used as a marker for effector and memory T cells.
Cholestyramine
A bile acid-binding resin that is used as a cholesterol-lowering agent.
coliforms
Aerobic or facultatively anaerobic, gram-negative, non– endospore-forming, rod-shaped bacteria that ferment lactose with acid and gas formation within 48 hours at 35°C.
common ion effect
The tendency for a common ion to decrease the solubility of an ionic compound or to decrease the ionization of a weak acid or weak base.
contact process
An industrial method for the production of sulfuric acid.
Curtius rearrangement
The conversion of an acid chloride into an amine by reaction with azide ion, followed by heating with water.
denaturing
The process by which a protein loses its complex tertiary and quaternary structure by heat, acids, salts, or solvents.
Diazotization
The conversion of a primary amine, RNH2, into a diazonium ion, RN2+, by treatment with nitrous acid.
diprotic acid
An acid that contains two ionizable protons.
Enterohepatic circulation
The cycling of bile acids (and other compounds) through liver and intestine.
equivalence point
The point in the titration at which the added solute completely reacts with the solute present in the solution; for acid–base titrations, the point in the titration when the number of moles of base is stoichiometrically equal to the number of moles of acid.
extremophile
A microorganism that lives in environmental extremes of temperature, acidity, alkalinity, salinity, or pressure.
Fischer esterification reaction
The acid-catalyzed nucleophilic acyl substitution reaction of a carboxylic acid with an alcohol to yield an ester. Fischer projection uses a cross to represent the chirality center. The horizontal arms of the cross represent bonds coming out of the plane of the page, and the vertical arms of the cross represent bonds going back into the plane of the page.
GABAergic
Describing neurons or synapses that produce and release gamma-aminobutyric acid.
Hell–Volhard–Zelinskii (HVZ) reaction
The reaction of a carboxylic acid with Br2 and phosphorus to give an a-bromo carboxylic acid.
Heteroduplex
A double-stranded nucleic acid containing one or more mismatched (noncomplementary) base pairs.
heterolactic
Describing an organism that produces lactic acid and other acids or alcohols as end-products of fermentation; e.g., Escherichia.
homolactic
Describing an organism that produces only lactic acid from fermentation; e.g., Streptococcus.
Hydration
Addition of water to a molecule, such as occurs when alkenes are treated with aqueous sulfuric acid to give alcohols.
inorganic
Chemical substance that is not organic; e.g., water, acids, bases.
lactic acid fermentation
A catabolic process, beginning with glycolysis, that produces lactic acid to reoxidize NADH.
M protein
A heat- and acid-resistant protein of streptococcal cell walls and fibrils.
malolactic fermentation
The conversion of malic acid to lactic acid by lactic acid bacteria.
Malonic ester synthesis
The syn thesis of a carboxylic acid by alkylation of an alkyl halide with diethyl malonate, followed by hydrolysis and decarboxylation.
Marker rescue
Replacement of all local nucleic acids that include a mutation with wild-type nucleic acid. (Chapter 3)
Marker transfer
Introduction of a mutation by replacement of a segment of viral nucleic acid with one containing the mutation. (Chapter 3)
metabolic acid
Acid produced as a by-product of metabolism; e.g., ketoacid.
mismatch
A base pair in a nucleic acid that cannot form a normal Watson-Crick pair.
monoprotic acid
An acid that contains only one ionizable proton.
MR1
A ‘non-classical’ MHC class Ib molecule that binds certain folic acid metabolites produced by bacteria for recognition by mucosal associated invariant T (MAIT) cells.
Niacin
Nicotinic acid; also used as a generic name for nicotinic acid and nicotinamide.
nonenveloped virus
Virus consisting of a nucleic acid core and a protein capsid only.
Nonketotic hyperosmolar coma
A metabolic emergency in patients with type 2 diabetes with hyperglycemia and dehydration but no acidosis.
nucleic acid amplification test (NAAT)
Test to identify an organism without culturing by making copies (amplifying) nucleic acid sequences that are specific for the organism being detected.
Nucleoprotein
Conjugated protein composed of nucleic acid and protein; the material of which the chromosomes are made.
nucleotide (or nucleoside) analog
A chemical that is structurally similar to the normal nucleotide or nucleoside in nucleic acids but with altered base-pairing properties.
Ostwald process
An industrial process used for commercial preparation of nitric acid.
oxyacid
An acid composed of hydrogen and an oxyanion.
Ozonide
The product initially formed by addition of ozone to a carbon–carbon double bond. Ozonides are usually treated with a reducing agent, such as zinc in acetic acid, to produce carbonyl compounds.
Packaging signal
Nucleic acid sequence or structural feature directing incorporation of a viral genome into a virus particle. (Chapter 13)
Para-aminobenzoic acid (PABA)
A constituent of folic acid.
percent ionization
The ratio of the ionized acid concentration to the initial acid concentration, multiplied by 100%.
Permissive
Able to support virus reproduction when viral nucleic acid is introduced; refers to cells. (Chapter 2)
pH scale
Common measure of the acidity of a solution: “p” refers to power of 10, “H” to hydrogen. Defined as the negative logarithm of the hydrogen ion concentration in moles per liter (M). pH = –log [H+]. Thus a solution of pH 3 will contain 10–3 M hydrogen ions. pH less than 7 is acidic and pH greater than 7 is alkaline.
phenol OH
Also called carbolic acid.
phosphate group
A portion of a phosphoric acid molecule attached to some other molecule, P smallest size, for in text.
phosphodiester linkage
A chemical grouping that contains two alcohols esterified to one molecule of phosphoric acid, which thus serves as a bridge between them.
Phosphoric acid anhydride
A substance that contains PO2PO link, analogous to the CO2CO link in carboxylic acid anhydrides.
Phytosiderophore
Metal chelator of the mugineic acid family released by roots of grasses to mobilize iron.
pK value
The negative logarithm of the dissociation constant for an acid.
polyprotic acid
An acid that contains more than one ionizable proton and releases them sequentially.
Primary bile acids
Bile acids that are synthesized by the liver.
proton donor
The donor of a proton in an acid-base reaction; that is, an acid.
RGD sequence
Tripeptide sequence of arginine-glycineaspartic acid that forms a binding site for integrins; present in fibronectin and some other extracellular proteins.
Saponification
An old term for the base-induced hydrolysis of an ester to yield a carboxylic acid salt.
Secondary bile acids
Bile acids that are synthesized from the primary bile acids by intestinal bacteria.
Sialic acid
One of a group of more than 300 carbohydrates based on acetylneuramic acid.
SMVT
An intestinal transport protein for biotin and pantothenic acid absorption.
Sodium urate
The poorly soluble uric acid salt that deposits in the joints of patients with gout.
specific acid-base catalysis
Acid or base catalysis involving the constituents of water (hydroxide or hydronium ions).
Stable isotope probing (SIP)
Application of substrates containing stable isotope labels (13C, 15N) to monitor substrate incorporation into cellular components (nucleic acids, proteins) of organisms / complex microbial communities aiming at the identification of active organisms / populations / community members.
strong acid
An acid that completely ionizes in solution.
Sulfonation
The substitution of a sulfonic acid group (-SO3H) onto an aromatic ring.
Suzuki–Miyaura reaction
The palladiumcatalyzed coupling reaction of an aromatic or vinylic halide with an aromatic or vinylic boronic acid.
titration curve
A plot of pH versus the equivalents of base added during titration of an acid.
TLR-1
Cell-surface Toll-like receptor that acts in a heterodimer with TLR-2 to recognize lipoteichoic acid and bacterial lipoproteins.
TLR-2
Cell-surface Toll-like receptor that acts in a heterodimer with either TLR-1 or TLR-6 to recognize lipoteichoic acid and bacterial lipoproteins.
TLR-6
Cell-surface Toll-like receptor that acts in a heterodimer with TLR-2 to recognize lipoteichoic acid and bacterial lipoproteins.
triprotic acid
An acid that contains three ionizable protons.
uricotelic
Excreting excess nitrogen in the form of urate (uric acid).
Uronic acid pathway
The pathway of glucuronic acid metabolism.
V-type pumps
Turbine-like protein machines constructed from multiple different subunits that use the energy of ATP hydrolysis to drive transport across a membrane. The V-type proton pump transfers H+ into organelles such as lysosomes to acidify their interior.
volatile acid
(vol′ă-til) In the body, an acid produced from carbon dioxide; e.g., carbonic acid.
Waxes
A mixture of esters of long-chain carboxylic acids with long-chain alcohols.
weak acid
An acid that does not completely ionize in water.
Abscisic acid (ABA)
A phytohormone involved in the responses of plants to abiotic and biotic stress. It regulates stress-related genes and is also responsible for stomata closure during drought. Its biosynthesis starts in the plastids from xanthophylls.
Acid anhydrides
A type of functional group with two acyl groups bonded to a common oxygen atom, RCO2COR’.
Acid halides
A type of functional group with an acyl group bonded to a halogen atom, RCOX.
Acid phosphatase
A marker for prostatic cancer.
acid-base balance
Maintaining hydrogen ion concentration of body fluids within normal limits; also called pH balance.
acidic dye
A salt in which the color is in the negative ion; used for negative staining.
acidophile
A bacterium that grows below pH 4.
Brønsted–Lowry acid
A substance that donates a hydrogen ion (proton; H+) to a base.
Crassulacean acid metabolism (CAM)
Function in some plants living in arid conditions. In these plants stomata open during night. Then CO2 is transformed to malate and stored. During daytime stomata are closed to avoid loss of water and CO2 is liberated from malate and fed into the Calvin cycle.
general acid-base catalysis
Catalysis involving proton transfer(s) to or from a molecule other than water.
lactic acid
The end product of the fast glycolytic system that is often associated with fatigue because it can inhibit calcium binding to troponin or interfere with cross-bridge formation.
lipoteichoic acids
Components of bacterial cell walls that are recognized by Toll-like receptors.
Oxalic acid
A component of kidney stones that can be formed from glycine.
Pangamic acid
Ill-defined substance(s), originally derived from apricot pits, with unsubstantiated claims for a variety of health benefits
RAE1 (retinoic acid early inducible 1) protein family
Several murine MHC class Ib proteins; these are orthologs of human RAET1 family proteins, including H60 and MULT1, and are ligands for murine NKG2D.
Uric acid nephropathy
Kidney damage caused by urate deposits.
