Shared Flashcard Set

Details

Bio chapter 5
Test 1 Flashcards Chapter 5
46
Biology
Undergraduate 1
01/21/2012

Additional Biology Flashcards

 


 

Cards

Term

 

Macromolecule

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

 

polymer

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

 

monomer

Definition
The subunit that serves as the building block of a polymer
Term

 

enzyme

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

 

dehydration reaction

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

 

hydrolysis

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

 

carbohydrate

Definition
A sugar (monosaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides)
Term

 

monosaccharide

Definition
The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, monosaccharides have molecular formulas thatare generally some multiple of CHO
Term

 

disaccharide

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

 

glycosidic linkage

Definition
A covalent bond formed between two monosaccharides by a dehydration reaction
Term

 

polysaccharides

Definition
A polymer of many monosaccharides, formed by dehydration reactions
Term

 

starch

Definition
A storage polysaccharide in plants, consisting entirely of glucose monomers joined by α glycosidic linkages
Term

 

glycogen

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

 

cellulose

Definition
A structural polysaccharide of plant cell walls, consisting of glucose monomers joined by β glycosidic linkages
Term

 

chitin

Definition
A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods
Term

 

lipid

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

 

fat

Definition
A lipid consisting of three fatty acids linkedtoone glycerol molecule; also called a triacylglycerol or triglyceride
Term

 

fatty acid

Definition
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
Term

 

triacylglycerol

Definition
A lipid consisting of three fatty acids linked to one glycerol molecule; also called a fat or triglyceride
Term

 

saturated fatty acid

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

 

unsaturated fatty acid

Definition
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
Term

 

trans fat

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

 

phospholipid

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

 

steroid

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

 

cholesterol

Definition
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
Term

 

catalyst

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

 

polypeptide

Definition
A polymer of many amino acids linked together by peptide bonds
Term

 

protein

Definition
A biologically functional  molecule consisting of one or more poly-peptides folded and coiled into a specific  three-dimensional structure
Term

 

amino acid

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

 

peptide bond

Definition
The covalent bond between the carboxyl group on one amino acid and the amino group on another, formed by a dehydration reaction
Term

 

sickle cell disease

Definition
A recessively inherited human blood disorder in which a single nucleotide change in the '-globin gene causes hemoglobin to aggregate, changing red blood cell shape and causing multiple symptoms in afflicted individuals
Term

 

denaturation

Definition
In proteins, a process in which a protein loses its native shape due to the disruption of 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
Term

 

chaperonin

Definition
A protein complex that assists in the proper folding of other proteins
Term

 

X-ray crystallography

Definition
A technique used to study the three-dimensional structure of molecules. It depends on the diffraction of an X-ray beam by the individual atoms of a crystallized molecule
Term

 

gene

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

 

nucleic acid

Definition
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
Term

 

deoxyribonucleic acid (DNA)

Definition
A nucleic acid molecule, usually a double-stranded helix, in which each polynucleotide strand consists of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T); capable of being replicated and determining the inherited structure of a cell’s proteins
Term

 

ribonucleic acid (RNA)

Definition
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-stranded; functions in protein synthesis, gene regulation, and as the genome of some viruses
Term

 

polynucleotide

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

 

nucleotide

Definition
The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and one or more phosphate groups
Term

 

pyrmidine

Definition
One of two types of nitrogenous bases found in nucleotides, characterized by a six-membered ring. Cytosine (C), thymine (T), and uracil (U) are pyrimidines
Term

 

purine

Definition
One of two types of nitrogenous bases found in nucleotides, characterized by a six-membered ring fused to a five- membered ring. Adenine (A) and guanine (G) are purines
Term

 

deoxyribose

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

 

ribose

Definition
The sugar component of RNA nucleotides
Term

 

double helix

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

 

antiparallel

Definition
Referring to the arrangement of the sugar-phosphate backbones in a DNA double helix (they run in opposite 5' S 3' directions)
Supporting users have an ad free experience!