CIBI 3031 Terms to Know Instructor: Kristin Peterson

Chapter 3: Glossary of selected key terms (términos clave selectos)

alcohol / alcohol

Organic compound containing one or more hydroxyl groups (-OH); it dissolves readily in water. Sugars are examples.

amino acid / aminoácido

Organic compound with an H atom, amino group, acid group, and R group, all covalently bonded to a carbon atom. Subunit of polypeptide chains.

ATP / ATP

Nucleotide with adenine, ribose, and three phosphate groups; delivers energy to most energy-requiring metabolic reactions.

carbohydrate / carbohidrato

Molecule of carbon, hydrogen, and oxygen mostly in a 1:2:1 ratio. Main kinds are monosaccharides, oligosaccharides, and polysaccharides. They are structural materials, energy stores, and transportable energy forms.

coenzyme / coenzima

Enzyme helper; a nucleotide that transfers electrons and H atoms stripped from substrates to a different reaction site.

condensation reaction / reacción de condensación

Covalent bonding of two molecules into a larger one; water often forms as a by-product.

denaturation / desnaturalización

Loss of a molecule's three-dimensional shape as weak bonds (e.g., hydrogen bonds) are disrupted.

DNA / ADN

Of cells and many viruses, the molecule of inheritance. H bonds join its two helically twisted nucleotide strands, one of which has instructions (in its base sequence) for synthesizing all of the enzymes and other proteins required to build and maintain cells.

domain / dominio

Part or all of a polypeptide chain that forms a structurally stable, functional unit.

enzyme / enzima

A type of protein or one of the few RNAs that catalyze reactions between substances, most often at functional groups.

fat / grasa

Lipid with a glycerol head and one, two, or three fatty acid tails. Saturated tails have single covalent bonds in the carbon backbone; unsaturated tails have one or more double bonds.

fatty acid / ácido graso

Molecule with a backbone of up to 36 carbon atoms, a carboxyl group (-COO- or -COOH) at one end, and hydrogen atoms at most or all of the other bonding sites.

functional group / grupo funcional

An atom or a group of atoms that is covalently bonded to the carbon backbone of an organic compound and that influences its chemical behavior.

HLA / HLA

One of a class of recognition proteins important in immune responses.

hydrocarbon / hidrocarburo

An organic compound that has only hydrogen bonded to a carbon backbone.

hydrolysis / hidrólisis

Cleavage reaction that breaks covalent bonds and splits a molecule into two or more parts. H⁺ and OH^- (from a water molecule) are often attached to the newly exposed bonding sites.

lipid / lípido

A mostly greasy or oily hydrocarbon; resists dissolving in water but dissolves in nonpolar substances. All cells use lipids as storage forms of energy, structural materials as in membranes, and cell products.

monomer / monómero

Small molecule used as a subunit of polymers, such as sugar monomers of starch.

monosaccharide / monosacárido

One of the simple carbohydrates (e.g., glucose).

nucleic acid / ácido nucleico

Single- or doublestranded chain of four kinds of nucleotides joined at their phosphate groups. Nucleic acids (e.g., DNA, RNA) differ in base sequences.

nucleotide / nucleótido

Small organic compound with deoxyribose (a five-carbon sugar), a nitrogenous base, and a phosphate group. Monomer for adenosine phosphates, nucleotide coenzymes, and nucleic acids.

oligosaccharide / oligosacárido

Shortchain carbohydrate of two or more covalently bonded sugar monomers (e.g., disaccharides).

organic compound / compuesto orgánico

A molecule containing carbon and at least one hydrogen atom.

phospholipids / fosfolípido

Organic compound that has a glycerol backbone, two fatty acid tails, and a hydrophilic head of two polar groups (one being phosphate). Phospholipids are the main structural component of cell membranes.

polymer / polímero

Large molecule of three to millions of monomers of the same or different kinds.

polypeptide chain / cadena polipeptídica

An organic compound of three or more amino acids joined by peptide bonds; atoms of its backbone have this pattern: -N-C-C-N-C-C-. All proteins are composed of one or more polypeptide chains.

polysaccharide / polisacárido

Straight or branched chain of many covalently linked sugar units of the same or different kinds. In nature, the most common types are cellulose, starch, and glycogen.

protein / proteína

Organic compound of one or more polypeptide chains folded and twisted into a globular or fibrous shape, overall.

RNA / ARN

Any of a class of single-stranded nucleic acids that function in transcribing and translating the genetic instructions encoded in DNA into proteins.

sterol / esterol

Lipid with a rigid backbone of four fused carbon rings (e.g., cholesterol). Sterols differ in the number, position, and type of their functional groups.

triglyceride / triglicérido

(neutral fat) A neutral fat; a lipid with three fatty acid tails attached to a glycerol unit. Triglycerides are the animal body's most abundant lipid and its richest energy source.

wax / cera

Organic compound; long-chain fatty acids packed together and attached to long-chain alcohols or carbon rings. Waxes have a firm consistency and repel water.