Biology 101

  1. biology
    the scientific study of life
  2. evolution
     the idea that living species are descendants of ancestral species that were different from the present day ones
  3. emergent properties
    new properties that arise with each step upward in the hierarchy of life owing to the arrangement and interactions of parts as complexity increases.
  4. systems biology
    an approach to studying biology that aims to model the dynamic behavior of whole biological systems based on a study of the interactions among the systems parts
  5. bacteria
    one of two prokaryotic domains the other being archaea
  6. archaea
     one of two prokaryotic domains the other being bacteria (extreme environments)
  7. eukarya
    the domain that includes all eukaryotic organisms (kingdoms: Planate, Fungi, Animal)
  8. natural selection
    a process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits. 
  9. Polar covalent bonds
    a covalent bond between atoms that differ in electronegativity. The shared electrons are pulled closer to the more electronegative atom making it slightly negative and the other atom slightly positive
  10. Polar molecule
    a molecule (such as water) with an uneven distribution of charges in different regions of the molecule. 
  11. Macromolecules
    a giant molecule formed by the joining of smaller molecules usually by a dehydration reaction.  Polysaccharides, proteins, and nucleic acids are macromolecules
  12. polymer
    a long molecule consisting of many similar or identical monomers linked together by covalent bonds.
  13. monomers
    the subunit that serves as the building lock for a polymer
  14. enzymes
    a macromolecule serving as a catalyst a chemical agent that increases the rate of a reaction without being consumed by it.  Most are proteins
  15. Dehydration reaction
    a chemical reaction in which two molecules become covalently bonded to each other with the removal of a water molecule
  16. hydrolysis
    a chemical reaction that breaks bonds between two molecules by the addition of water.  Functions in disassembly of polymers to monomers
  17. carbohydrates
    a sugar (monossaccharide) or one of its dimers (disaccharides) or polymers (polysaccharides)
  18. monosaccharides
    the simplest carbohydrate active alone or serving as a monomer for disaccharides and polysaccharides.  Also known as simple sugars monosaccharides have molecular formulas that are generally some multiple of CH2O
  19. Disaccharide
    a double sugar consisting of two monosaccharides joned by a glycosidic linkage formed by a dehydration reaction
  20. Glycosidic linkage
    a covalent bond formed between two monosaccharides by a dehydration reaction
  21. Polysaccharides
    a polymer of many monosaccharides formed by dehydration reactions
  22. Starch
    a storage polysaccharide in plants consisting entirely of glucose monomers joined by alpha glycosidic linkages
  23. Cellulose
    a structural polysaccharide of plant cell walls consisting of glucose monomers joined by beta glycosidic linkages
  24. Chitin
    a structural polysaccharide consisting of amino sugar monomers found in many fungal cell walls and in the exoskeletons of all anthropods
  25. Lipids
    any group of large biological molecules including fats phospholipids and steroids that mix poorly if at all with water
  26. fat
    a lipid consisting of three fatty acids linked to one glycerol molecule.  Also called a triacylglycerol or triglyceride
  27. Fatty acid
    a carboxylic acid with a long carbon chain. Fatty acids vary in length and in the number and location of the double bonds.  Three fatty acids linked to a glycerol molecule form a fat molecule also known as a triacylglycerol or triglyceride
  28. Triacylglycerol
    a lipid consisting of three fatty acids linked to one glycerol molecule. Also called a fat or triglyceride
  29. Saturated fatty acid
    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
  30. Unsaturated fatty acid
    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.
  31. Trans fat
    an unsaturated fat formed artificially during hydrogenation of oils containing, one or more trans double bonds
  32. Phospholipids
    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
  33. Steroids
    a type of lipid characterized by a carbon skeleton consisting of four fused rings with various chemical groups attached
  34. Cholesterol
    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
  35. Catalysts
    a chemical agent that selectively increases the rate of a reaction without being consumed by it
  36. Polypeptides
    a polymer of many amino acids linked together by peptide bonds
  37. protein
    a biologically functional molecule consisting of one or more polypeptides folded and coiled into a specific 3D structure
  38. Amino acid
    an organic molecule possessing both a carboxyl and an amino group. Amino acids serve as the monomers of polypeptides
  39. Peptide bond
    a polymer of many amino acids linked together by peptide bonds
  40. Primary structure
    the level of protein structure referring to the specific linear sequence  of amino acids
  41. Secondary structure
    regions of repetitive coiling or folding of the polypeptide backbone of a protein due to hydrogen bonding between constituents of the backbone (not the side chains)
  42. Alpha helix
    a coiled region constituting one form of the secondary structure of proteins arising from a specific pattern of hydrogen bonding between atoms of the polypeptide backbone (not the side chains)
  43. Beta pleated sheet
    one form of the secondary structure of proteins in which the polypeptide chain folds back and forth. Two regions of the chain lie parallel to each other and are held together by hydrogen bonds between atoms of the polypeptide backbone (not the side chains)
  44. Tertiary structure
    the overall shape of a protein molecule due to interactions of amino acid side chains including hydrophobic interactions ionic bonds hydrogen bonds and disulfide bridges
  45. Hydrophobic interaction
    a type of weak chemical interaction caused when molecules that do not mix with water coalesce to exclude water
  46. Disulfide bridges
    a strong covalent bond formed when the sulfur of one cysteine monomer bonds
  47. Quaternary structure
    the particular shape of a complex aggregate protein defined by the characteristic 3D arrangement of its constituent subunits each a polypeptide
  48. Collagen
    a glycoprotein in the extracellular matrix of animal cells that forms strong fibers found extensively in connective tissue and bone. The most abundant protein in the animal kingdom
  49. Sickle-cell disease
    a recessively inherited human blood disorder in which a single nucleotide change in the beta globin gene causes hemoglobin to aggregate changing red blood cell shape and causing multiple symptoms in afflicted individuals
  50. Denaturation
    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 conditions of pH, salt concentration, or temperature
  51. Chaperonins
    a protein complex that assists in the proper folding of other proteins
  52. X-ray crystallography
     a technique used to study the 3D structure of molecules.  It depends on the diffraction of an xray beam by the individual atoms of crystallized molecule
  53. Light microscope
    an optical instrument with lenses that refract (bend) visible light to magnify images of specimens
  54. organelles
    any of several membrane enclosed structures with specialized functions suspended in the cytosol of eukaryotic cells
  55. electron microscope
     a microscope that uses magnets to focus an electron beam on or through a specimen resulting in a practical resolution of a hundredfold greater than that of alight microscope 
  56. Scanning electron microscope
    a microscope that uses an electron beam to scan the surface of a sample coated with metal atoms to study details of its topography
  57. Transmission electron microscope
    a microscope that passes an electron beam through very thin sections stained with metal atoms and is primarily used to study the internal ultrastructure of cells
  58. Cell fractionation
    the disruption of a cell and separation of its parts by centrifugation at successively higher speeds
  59. Cytosol
    the semifluid portion of the cytoplasm
  60. Eukaryotic cell
    a type of cell with a membrane enclosed nucleus and membrane enclosed organelles. Organisms with eukaryotic cells (fungi protists plants and animals) are all called eukaryotes
  61. Prokaryotic cell
    a type of cell lacking a membrane enclosed nucleus and organelles. Organisms with prokaryotic cells (bacteria and archaea) are called prokaryotes
  62. Nucleoid
     a non membrane bound region in a prokaryotic cell where DNA is concentrated
  63. Plasma membrane-
    the membrane at the boundary of every cell that acts as a selective barrier regulating the cells chemical composition
  64. Ribosomes
    a complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm.  Consists of a large and small subunit.  In eukaryotic cells each subunit is assembled in the nucleolus
  65. Nucleus
    the organelle of a eukaryotic cell that contains the genetic material in the form of chromosomes, made up of chromatin
Card Set
Biology 101
Molecules of Life and Cellular Organization