BIOCHEMISTRY  NOTES  

                                                               -­‐UNIT  2-­‐    

ATOMS  

• ________________-­‐  the  basic  unit  of  matter.  

• Contains  subatomic  particles  

o _____________________  (+  charge)  

o _____________________  (no  charge/neutral)  

o _____________________  (-­‐  charge)  

• Protons  and  neutrons  have  about  the  same  mass.    Electrons  are  much  ________________.  

• Atoms  have  equal  numbers  of  __________________________  and  ___________________________.  

o Because  these  particles  are  opposite  charges,  the  whole  atom  is  _______________.    

 

ELEMENTS  AND  ISOTOPES  

• ___________________-­‐  a  pure  substance  that  consists  of  only  one  type  of  atom.    Elements  

are  represented  by  a  1  or  2  letter  symbol.    (ie:  C  =  carbon)  

• The  number  of  ___________________  in  an  element  is  that  element’s  _______________________.      

o The  atomic  number  of  carbon  is  6,  therefore  carbon  has  6  protons  and  

consequently  6  neutrons.  

• Mass  Number-­‐  the  sum  of  the  number  of  ________________________  plus  the  number  of  

________________________.  

 

ISOTOPES  

• _________________-­‐  atoms  of  the  same  element  that  have  different  numbers  of  neutrons.  

o Isotopes  are  identified  by  their  _________________________________________________  

(ie:  carbon-­‐12,  carbon-­‐13,  carbon-­‐14)  

• The  _____________________________________________  of  the  masses  of  an  element’s  isotopes  is  

called  its  _____________________________.      

• Isotopes  have  the  same  number  of  _______________________,  so  all  isotopes  of  an  element  

have  the  same  ______________________________________.  

RADIOACTIVE  ISOTOPES  

• Some  isotopes  are  _____________________________.    This  means  that  

their  nuclei  are  unstable  and  break  down  at  a  continuous  rate  

over  time.  

 

IONS  

• _______________-­‐  an  atom  that  has  gained  or  lost  an  electron,  giving  it  a  positive  or  

negative  charge.  

o ___________________-­‐  a  positively  charged  ion  

o ___________________-­‐  a  negatively  charged  ion  

 

CHEMICAL  COMPOUNDS  

• _______________________-­‐  formed  by  the  chemical  combination  of  two  or  more  elements  

in  definite  proportions.  

o Compounds  are  typically  written  as  a  __________________________________________  

(ie:  NaCl,  CO2,  etc.)    This  gives  you  the  ratio  elements  in  the  compound.  

o The  physical  and  chemical  properties  of  a  compound  are  usually  very  

different  from  those  of  the  elements  form  which  it  is  formed.  

• Chemical  compounds  are  held  together  by  __________________,  which  are  formed  by  the  

_______________________  of  each  element.    

• The  electrons  that  are  available  to  form  bonds  are  called  _______________________________,  

and  are  on  the  ___________________________________________________________.  

 

CHEMICAL  BONDS  

• ___________________________________-­‐  formed  when  one  or  more  electrons  are  transferred  

from  one  atom  to  another.      

o Form  between  a  _____________________  and  a  _______________________.      

(between  a  __________________  and  an  _________________)  

 

 

NAMING  IONIC  COMPOUNDS  

• The  names  of  ionic  compounds  consist  of  the  names  of  the  ___________  that  make  up  

the  compounds.  

o Names  of  ______________________  are  the  ______________  as  the  elements  of  which  

they  are  composed.  

o Names  of  ___________________  are  _____________________  names  of  elements.    The  

difference  is  the  name’s  _______________________.    (____________)  

• An  ionic  compound  must  have  a  _______________________________________________.  

 

CLASS  PRACTICE  

• Na  +  F       _________________________________________________________________  

• Mg  +  O     _________________________________________________________________  

• K  +  I     _________________________________________________________________  

• Ca  +  S     _________________________________________________________________  

 

YOU  TRY  IT!  

• Li  +  O     _________________________________________________________________  

• Ca  +  Cl     _________________________________________________________________  

• K  +  Se     _________________________________________________________________  

• Mg  +  Br   _________________________________________________________________  

 

NAMING  IONIC  COMPOUNDS  

• Some  cations  (the  _______________________  metals)  must  show  their  charge.      

  ex:  FeO   _________________________________________________________________  

                                       Fe2O3   _________________________________________________________________  

 

CLASS  PRACTICE  

• TiN       _________________________________________________________________  

• NiS       _________________________________________________________________  

• Copper(III)oxide   _________________________________________________________________  

 

YOU  TRY  IT!  

• Iron(II)sulfide   _________________________________________________________________  

• Gold(III)bromide   _________________________________________________________________  

 

CHEMICAL  BONDS  

• _____________________________________________-­‐  results  when  electrons  are  shared  

between  atoms.  

o The  structure  that  results  when  atoms  are  joined  together  by  

covalent  bonds  is  called  a  _________________________.  

o Covalent  bonds  usually  form  between  __________________________________.      

o Covalent  bonds  are  the  _______________________  bonds  between  atoms.  

• ____________________  Covalent  Bond-­‐  atoms  share  _____  electrons,    

• ____________________  Covalent  Bond-­‐  atoms  share  _____  electrons.  

• ____________________  Covalent  Bond-­‐  atoms  share  _____  electrons.    

 

 

 

 

 

 

 

 

 

COVALENT  COMPOUNDS  

• Covalent  compounds  are  named  ___________________________than  ionic  compounds.  

• Unlike  ionic  compounds,  __________________________  compounds  use  __________________.  

• Prefixes  tell  how  many  ______________  of  each  element  are  in  the  molecule.  

• If  there  is  only  ________  atom  of  the  first  element,  the  name  does  not  get  a  _____________.      

• The  element  furthest  to  the  _______________  on  the  periodic  table  is  named  ______________  

and  ends  in  _____________.  

 

CLASS  PRACTICE  

• BF3   __________________________________________________________    

• N2O4   _________________________________________________________________  

• Si  I4   _________________________________________________________________  

 

YOU  TRY  IT!  

• P4S3   _________________________________________________________________  

• SeO2   _________________________________________________________________  

• As2O5   _________________________________________________________________  

 

CHEMICAL  BONDS  

• __________________________________________________-­‐  Hydrogen  can  form  a  special  type  of  

bonds  with  a    couple  of  unique  elements:      ____________________________  

• A  slight  attraction  that  develops  between  _________________________  charged  regions  of  

___________________________________.  

o Not  near  as  strong  as  ionic  or  covalent  bonds,  although  they  can  hold  

molecules  together,  especially  when  the  molecules  are  large.  

 

FORCES  BETWEEN  MOLECULES  

• ________________________________  Forces-­‐  between  atoms  of  two  different  molecules.  

o Ex:  _________________________________________________________________  

• ________________________________  Forces-­‐  between  atoms  of  the  same  molecule.  

o Ex:  _________________________________________________________________  

 

THE  WATER  MOLECULE  

• The  single  most  _______________________  compound  in  most  living  things.    

• Water  ___________________  as  it  freezes.  

• Water  is  a  ___________________  molecule  (equal  #  of  protons  and  electrons).  

 

 

• Water  is  ________________  because  there  is  an  ________________  distribution  of  

____________________  between  the  oxygen  and  hydrogen  atoms.      

o The  hydrogen  ends  of  the  molecule  are  slightly  __________________  and  the  

oxygen  end  is  slightly  _____________________.  

• Because  of  the  ______________________  charges,  polar  molecules  (such  as  water)  can  

___________________  each  other.  

• The  attraction  between  the  hydrogen  atom  on  one  molecule  and  the  oxygen  atom  on  

another  molecule  is  an  example  of  a  ________________________________________.  

 

PROPERTIES  OF  WATER  

• _______________________-­‐  an  attraction  between  molecules  of  the  same  substance.                  

(ex:  water  attracted  to  water)  

• _______________________-­‐  an  attraction  between  molecules  of  different  substances.            

(ex:  water  attracted  to  glass).      Ex:  meniscus  

• Water  also  has  a  high  _____________________________________  which  allows  it  to  form  a  

skin-­‐like  surface.  

o Water  has  a  high  surface  tension  due  to  the  strong  _________________________  

forces  between  water  molecules.  

o ____________________________-­‐  compound  that  lowers  surface  tension.      

Example:  any  type  of  cleaner  

• ___________________________________-­‐  the  force  that  allows  water  to  move  against  gravity.  

• Example:  water  being  absorbed  up  the  roots  in  plants.  

 

SOLUTIONS  AND  SUSPENSIONS  

• _______________________-­‐  composed  of  two  or  more  elements  or  compounds  that  are  

physically  mixed  together,  but  not  chemically  combined.  

• _______________________-­‐  all  components  are  evenly  distributed  throughout  the  solution.  

o ___________________-­‐  the  substance  that  is  dissolved.  

o ___________________-­‐  the  substance  in  which  the  solute  dissolves.  

• ____________________________-­‐  mixture  of  water  and  non-­‐dissolved  materials.  

 

ACIDS,  BASES,  AND  PH  

• _________________________-­‐  indicates  the  concentration  of  

H+  ions  in  solution.    This  scale  ranges  from  

________________.    

• __________________-­‐  have  a  pH  value  _____________________.      

o Strong  acids  have  a  pH  between  1-­‐3.    (ie:  HCl)  

o Acids  have  a  high  concentration  of  

___________________,  and  a  low  concentration  of  OH-­‐  

ions.  

• __________________-­‐  have  a  pH  value  ______________________.    

o Strong  bases  have  a  pH  between  11-­‐14.  

o Bases  have  a  high  concentration  of  ___________________,  and  a  low  concentration  

of  H+  ions.  

• ____________________-­‐  weak  acids  or  bases  that  can  react  with  strong  acids  or  bases  to  

prevent  sharp,  sudden  changes  in  pH.  

• ____________________-­‐  ___________________.  

o ____________________  has  a  neutral  pH.  

 

CARBON  COMPOUNDS  

• _____________________________________________-­‐  the  study  of  all  compounds  

that  contain  carbon.  

• ________________________________-­‐  made  from  thousand  of  smaller  

molecules.  

o ____________________________________-­‐  large  compounds  called  

polymers  are  built  by  joining  smaller  compounds  (called  

monomers)  together.  

• There  are  four  groups  of  organic  compounds  found  in  living  things:    

o ___________________________________-­‐  made  of  monosaccharides.  

o _________________-­‐  made  of  glycerol  and  fatty  acid.  

o __________________________________-­‐  made  of  nucleotides.  

o __________________-­‐  made  of  amino  acids.  

CARBOHYDRATES    

• ____________________________________-­‐  compounds  made  up  of  carbon,  hydrogen,  and  

oxygen  atoms,  usually  in  a  1:2:1  ratio.  

• Living  things  use  carbohydrates  as  their  main  source  of  __________________.  

• Plants  and  some  animals  also  use  carbohydrates  for  ____________________________________.    

(ie:  cellulose-­‐  in  plant  walls)  

• _____________________________________-­‐  single  sugar  molecules  

o ie:  glucose,  galactose,  fructose  

• _____________________________________-­‐  large  macromolecules  formed  

from  monosaccharides.  

o ie:  glycogen  (animal  starch),  cellulose  (plant  starch)  

 

LIPIDS  

• _________________-­‐  made  mostly  from  carbon  and  hydrogen  atoms,  which  combine  to  

form  fatty  acids  and  glycerol.  

• The  common  categories  of  lipids  includes  ___________,  ____________,  _________________,  and  

_______________________.  

• Lipids  can  be  used  to  __________________________________.      

• If  each  carbon  atom  in  a  lipid’s  fatty  acid  chain  is  joined  to  another  carbon  atom  by  a  

single  bond,  the  lipid  is  said  to  be  _________________________,  because  it  contains  the  

maximum  number  of  hydrogen  atoms.    If  there  is  at  least  one  C=C,  they  are  said  to  

be  ________________________________.  

 

NUCLEIC  ACIDS  

• ___________________________________-­‐  macromolecules  containing  hydrogen,  oxygen,  

carbon,  and  phosphorous.  

• Nucleic  acids  are  polymers  assembled  from  individual  monomers  known  as  

_________________________________.    

 

 

 

• Nucleotides  consist  of  three  parts:    

o ______________________________________________  

o ______________________________________________  

o ______________________________________________  

•  Nucleic  acids  store  and  transmit  hereditary  or  genetic  

information  as  ___________  and  ___________  and  help  control  

the  ________________________________________________.  

 

PROTEINS  

• ________________________-­‐  macromolecules  that  contain  nitrogen,  carbon,  hydrogen,  and  

oxygen.  

• Proteins  are  made  of  molecules  called  _________________________________  which  are  held  

together  by  __________________________________.      

• Amino  acids  are  compounds  with  an  _________________________________________  on  one  end  

and  a  ____________________________________________  on  the  other  end.  

 

 

 

 

 

 

 

• The  instructions  for  arranging  amino  acids  into  many  different  proteins  are  stored  

in  DNA.      

• Each  protein  has  a  specific  role.      

o Some  proteins  control  the  ____________________________________________  and  

_____________________________________________    

o Some  are  used  to  _________________________________________________________.      

o Others  ____________________________________________________  into  or  out  of  the  cells.  

o Some  help  _______________________________________.  

• Proteins  have  4  levels  of  organization:  primary,  secondary,  tertiary,  and  quaternary.  

CHEMICAL  REACTIONS  

• ________________________________________-­‐  a  process  that  changes,  or  transforms  one  set  of  

chemicals  into  another.  

o ________________________-­‐  the  elements  or  compounds  that  enter  into  a  chemical  

reaction.    (on  the  left  of  the  equation)  

o ________________________-­‐  the  elements  or  compounds  produced  by  a  chemical  

reaction.    (on  the  right  of  the  equation)  

• Chemical  reactions  always  involve  changes  in  the  chemical  bonds  that  join  atoms  in  

compounds.  

 

ENERGY  IN  REACTIONS  

• Break  Bonds  =  _________________________________  

• Form  Bonds  =  __________________________________  

• Chemical  reactions  that  ______________________  energy  often  occur  spontaneously.    

Chemical  reactions  that  __________________  energy  will  not  occur  without  a  source  of  

energy.  

 

ACTIVATION  ENERGY  

• ______________________________________-­‐  the  energy  that  is  needed  to  get  a  reaction  started.      

               

         ENDERGONIC                                                                EXERGONIC  

 

 

 

 

 

 

 

 

 

 

ENZYMES  

• ___________________-­‐  a  substance  that  speeds  up  a  chemical  

reaction.      

o Catalysts  work  by  lowering  a  reaction’s  

______________________________________.  

• ___________________-­‐  proteins  that  act  as  biological  catalysts.      

o Enzymes  ______________________  chemical  reactions  

that  take  place  in  cells.  

 

ENZYME  ACTION  

• Enzymes  are  very  ______________________,  generally  catalyzing  only  1  chemical  reaction.      

• ______________________________-­‐  the  reactants  of  enzyme-­‐catalyzed  reactions.  

 (what  the  enzyme  acts  on)  

• _______________________________-­‐  place  on  the  enzyme  where  the  substrate  binds.      

 

 

 

 

 

 

 

 

 

 

REGULATION  OF  ENZYME  ACTIVTY  

• Enzymes  work  best  at  certain  _________  values.  

• Many  enzymes  are  affected  by  changes  in  ______________________________.    

• Enzymes  play  essential  roles  in  regulating  chemical  pathways,  making  materials  

that  cells  need,  releasing  energy,  and  transferring  information.