2. The Composition of Cells Flashcards
A protein that forms pores through a membrane.
channel protein
A polymer of N-acetylglucosamine residues that is the principal component of fungal cell walls.
chitin
The principal structural component of the plant cell wall, a linear polymer of glucose residues linked by beta (1-4) glycosidic bonds.
cellulose
A protein that selectively binds and transports small molecules across a membrane.
carrier protein
A molecule with the formula (CH2O)n.
carbohydrate
A molecule that has both hydrophobic and hydrophilic regions.
amphipathic
Monomeric building blocks of proteins, consisting of carbon atom bound to a carboxyl group, an amino acid, a hydrogen atom, and a distinctive side chain.
amino acid
A purine that base-pairs with either thymine or uracil.
adenine
The transport of molecules in an energetically unfavorable direction across a membrane coupled to the hydrolysis of ATP or other source of energy.
active transport
The five-carbon sugar of DNA.
2’-deoxyribose
A transmembrane domain formed by the folding of beta sheets into a barrel-like structure.
β-barrel
A sheetlike secondary structure of a polypeptide chain, formed by hydrogen bonding between amino acids located in different regions of the polypeptide.
β sheet
A coiled secondary structure of a polypeptide chain formed by hydrogen bonding between amino acids separated by four residues.
Alpha helix
A lipid consisting of four hydrocarbon rings. __________ is a major constituent of animal cell plasma membranes and the precursor of steroid hormones.
cholesterol
A pyrimidine that base-pairs with guanine.
cytosine
The genetic material of the cell.
deoxyribonucleic acid (DNA)
A folded three-dimensional region of a protein that forms the basic unit of tertiary structure.
domain
A long hydrocarbon chain usually linked to a carboxyl group (COO-)
fatty acid
A model of membrane structure in which proteins are inserted in a fluid phospholipid bilayer.
fluid mosaic model
The systematic analysis of entire cell genomes.
genomics
A phospholipid consisting of two fatty acids bound to a glycerol molecule.
glycerol phospholipid
A polymer of glucose residues that is the principal storage of carbohydrates in animals.
glycogen
A lipid consisting of two hydrocarbon chains linked to a polar head group containing carbohydrates.
glycolipid
The bond formed between sugar residues in oligosaccharides or polysaccharides.
glycosidic bond
A purine that base-pairs with cytosine.
guanine
Soluble in water.
hydrophilic
Not soluble in water.
hydrophobic
A protein embedded within the lipid bilayer of cell membranes.
integral membrane protein
Member of a group of hydrophobic molecules that function as energy storage molecules, signaling molecules, and the major components of cell membranes
lipid
A method for identifying compounds based on accurate determination of their mass. _____ __________ is commonly used for protein identification.
mass spectrometry
A simple sugar with the basic formula (CH2O)n.
monosaccharide
A purine or pyrimidine base linked to a sugar (ribose or dexyribose).
nucleoside
A phosphorylated nucleoside.
nucleotide
A short polymer of only a few nucleotides.
oligonucleotide
A short polymer of only a few sugars.
oligosaccharide
The transport of molecules across a membrane in the energetically favorable direction.
passive transport
The bond joining amino acids in polypeptide chains.
peptide bond
A protein that is indirectly associated with cell membranes by protein-protein inter-action.
peripheral membrane protein
A bond between the 5’-phosphate of one nucleotide and the 3’-hydroxyl of another.
phosphodiester bond
One of a family of molecules that are the principal components of cell membranes, consisting of two hydrocarbon chains (usually fatty acids) joined to a polar head group containing phosphate.
phospholipid
The basic structure of biological membranes in which the hydrophobic tails of phospholipids are buried in the interior of the membrane and their polar head groups are exposed to the aqueous solution on either side.
phospholipid bilayer
A polymer containing up to millions of nucleotides.
polynucleotide
A polymer of amino acids.
polypeptide
A polymer containing thousands of sugars.
polysaccharide
The sequence of amino acids in a polypeptide chain.
primary structure
A polypetide with a unique amino acid sequence.
protein
All of the proteins expressed in a given cell.
proteome
Large-scale analysis of cell proteins.
proteomics
One of the types of bases present in nucleic acids. The ________ are adenine and guanine.
purine
One of the types of bases present in nucleic acids. The __________ are cytosine, thymine, and uracil.
pyrimidine
The interactions between polypeptide chains in proteins consisting of more than one polypeptide.
quaternary structure
A polymer of ribonucleotides.
ribonucleic acid (RNA)
The five-carbon sugar found in RNA.
ribose
The regular arrangement of amino acids within localized regions of a polypeptide chain.
secondary structure
A phospholipid consisting of two hydrocarbon chains bound to a polar head group containing serine.
sphingomyelin
A polymer of glucose residues that is the principle storage form of carbohydrates in plants.
starch
A member of a group of hydrophobic hormones, including estrogen and testosterone, that are derivatives of cholesterol.
steroid hormone
A new field of biology in which large-scale experimental approaches are combined with quantitative analysis and modeling to study complex biological systems.
systems biology
The three-dimensional folding of a polypeptide chain that gives the protein its functional form.
tertiary structure
A pyrimidine found in DNA that base-pairs with adenine.
thymine
An integral membrane protein that spans the lipid bilayer and has portions exposed on both sides of the membrane.
transmembrane protein
Three fatty acids linked to a glycerol molecule.
triacylglycerol
A method for separating cell proteins based on both charge and size.
2-D gel electrophoresis
A pyrimidine found in RNA that base-pairs with adenine.
uracil
A method in which diffraction pattern of X-rays is used to determine the arrangement of individual atoms within a molecule.
X-ray crystallography
