Key terms

• What is absorption in biological terms?

  The passage of molecules through the gut wall
• How is accuracy defined in measurements?

  Closeness of a reading to the true value
• What is activation energy?

  Minimum energy for a chemical reaction
• What does active transport require?

  Energy from ATP produced by respiration
• What is the active site of an enzyme?

  Specific site where substrate binds
• What is the function of active transport?

  Movement of molecules against a concentration gradient
• What does ATP stand for?

  Adenosine triphosphate
• What is the role of ATP in cells?

  Provides energy through hydrolysis
• What is adhesion in biological terms?

  Attraction between water and hydrophilic molecules
• What does affinity refer to in biology?

  Degree of attraction between two molecules
• What are analogous structures?

  Similar function but different developmental origin
• What is an anticodon?

  Group of three bases on a tRNA molecule
• What does antiparallel mean in biology?

  Parallel but facing in opposite directions
• What is the apoplast pathway?

  Pathway of water through non-living spaces
• What is the function of the atrio-ventricular node (AVN)?


  Conducts electrical excitation between atria and ventricles
• What is an autotroph?

  Organism that synthesizes its own organic molecules
• What is the binomial system?

  Unique naming system with genus and species
• What does biodiversity refer to?

  Number of species and individuals in a region
• What is a biosensor?

  Device measuring chemical concentration using biomolecules
• What does bivalent refer to in meiosis?

  Association of two homologous chromosomes
• What is the Bohr effect?

  Shift of oxygen dissociation curve due to CO2
• What is capillarity?

  Movement of water up narrow tubes
• What are carnassials?

  Teeth with shearing action in carnivores
• What is the companion strip in plant cells?

  • Impermeable band of suberin
  • Blocks water movement in the apoplast
  • Forces water into the cytoplasm
• What is a catalyst?

  Molecule that alters reaction rates without change
• What is the cell cycle?

  Sequence of events between cell divisions
• What is a centromere?

  Region where two chromatids join
• What is a chemoautotroph?

  Organism using chemical energy for synthesis
• What is a chiasma?

  Site of DNA exchange during crossing over
• What is the chloride shift?

  Diffusion of chloride ions into red blood cells
• What is a chromatid?

  Identical copy of a chromosome before division
• What is a chromosome?

  Structure of DNA and proteins in the nucleus
• What is classification in biology?

  Grouping items based on similarities
• What is a codon?

  Triplet of bases coding for an amino acid
• What is cohesion in biology?

  Attraction of water molecules to each other
• What is the cohesion-tension theory?

  Mechanism of water movement in xylem
• What is competitive inhibition?

  Reduction of enzyme activity by similar molecules
• What is a condensation reaction?

  Combining molecules with water elimination
• What is a controlled variable?

  Factor kept constant in an experiment
• What is convergent evolution?

  • Development of similar features in unrelated organisms
  • Related to natural selection in similar environments
  • Results in analogous structures