AP Biology Unit 1

• polar covalent bond


  Bond that forms when electrons are shared unequally; like that between the oxygen atom and hydrogen atoms in a water molecule
• covalent bond


  Bond that forms when electrons between atoms are shared.
• nonpolar covalent bond


  Bond that forms when electrons are shared equally.
• chemical bond


  attraction between two atoms by transferring or sharing electrons to attain a stable electron configuration
• ion


  atom becomes charged when it gains or loses an electron
• electrons


  Atomic particles with a negative charge (-) found outside the nucleus of an atom.
• neutrons


  Atomic particles with a neutral (o) charge found in the nucleus of an atom.
• protons


  Atomic particles with a positive charge (+) found in the nucleus of an atom.
• atom


  Smallest form of an element that still displays its particular properties; consisting of a positively charged nucleus and a negatively charged electron cloud.
• adhesion


  the attraction of unlike molecules; water molecules are attracted to other polar surfaces

  
• cohesion


  the attraction of like substances; water molecules are attracted to other water molecules; this is due to the hydrogen bonding between water molecules

  
• the reason ice floats in liquid water


  less dense as a solid; hydrogen bonds form crystalline structure that keeps the water molecules separate

  
• evaporative cooling


  water carries the heat it absorbs away in sweat due to its high specific heat
• high specific heat


  property of water in which water changes temperature very slowly with changes in heat due to hydrogen bonding

  
• hydrophobic


  Term for substances that do not dissolve in water.
• hydrophilic


  Term for substances that dissolve in water.
• charge of the hydrogen atoms in a water molecule

  slightly positive
• charge of the oxygen atom in a water molecule

  slightly negative
• functional groups

  parts of organic molecules that are involved in chemical reactions
• hydrolysis


  the process of adding a water molecule to break a polymer into monomers

  
• dehydration synthesis


  reaction that links monomer molecules together, releasing a molecule of water for each bond formed
• monomer


  molecules that consist of a single unit
• polymer


  molecules that consist of many repeated monomers
• polar


  soluable in water
• nonpolar


  not soluable in water
• hydrocarbons


  carbon and hydrogen atoms that are covalently bonded that make them stable and nonpolar

  
• four


  number of covalent bonds carbon can form with other elements
• macromolecules

  large organic molecules
• glycosidic linkage


  covalent bond that forms between a monosaccharide and another molecule (like another monosaccharide)

  
• -ose


  suffix carbohydrates usually end in (gluc-ose, fruct-ose)
• hydrophobic head


  another name for the phosphate group in a phospholipid

  
• hydrophobic tail


  another name for the hydrocarbon chain in a phospholipid

  
• phospholipid


  lipid made of two hydrocarbon chains, glycerol, and a phosphate group

  
• functions of lipids

  long-term energy storage, insulation, part of the cell membrane, chemical messenger, waterproofing
• glycerol


  a carbon alcohol that is hydrophilic

  
• fatty acid

  building block of a lipid made of a hydrocarbon chain and a carboxyl group

  
• Carbon, Hydrogen, Oxygen (CHO)


  elements that makeup both Carbohydrates and Lipids
• lipids


  macromolecule made of carbon, hydrogen and oxygen (CHO) that is mostly nonpolar not soluble in water;
• hydrophobic R-groups


  move together to the interior of a protein, away from water
• four levels of a proteins structure

  primary structure, secondary structure, tertiary structure, quaternary structure