AP Biology Chapter 5  Smaller organic molecules join together to form larger molecules  macromolecules  4 major classes of macromolecules:  carbohydrates  lipids  proteins  nucleic acids

AP Biology Polymers  Long molecules built by linking repeating building blocks in a chain  monomers  building blocks  repeated small units  covalent bonds

AP Biology H2OH2O HO H HH How to build a polymer  Synthesis   joins monomers by “taking” H 2 O out  one monomer donates OH –  other monomer donates H +  together these form H 2 O  requires energy & enzymes enzyme Dehydration synthesis Condensation reaction

AP Biology H2OH2O HOH H H How to break down a polymer  Digestion   use H 2 O to breakdown polymers  reverse of dehydration synthesis  cleave off one monomer at a time  H 2 O is split into H + and OH –  H + & OH – attach to ends  requires enzymes  releases energy Hydrolysis Digestion enzyme

AP Biology Carbohydrates  Carbohydrates are composed of __, __, __ carbo - hydr - ate CH 2 O (CH 2 O) x C 6 H 12 O 6  Function:  fast energy u energy storage  raw materials u structural materials  Monomer: sugars  ex: sugars, starches, cellulose sugar C 6 H 12 O 6 (CH 2 O) x

AP Biology Functional groups determine function carbonyl ketone aldehyde carbonyl

AP Biology Sugar structure 5C & 6C sugars form rings in solution

AP Biology Simple & complex sugars  Monosaccharides  simple 1 monomer sugars  glucose  Disaccharides  2 monomers  sucrose  Polysaccharides  large polymers  starch OH H H HO CH 2 OH H H H OH O Glucose

AP Biology Building sugars  Dehydration synthesis | glucose | glucose monosaccharidesdisaccharide | maltose H2OH2O

AP Biology Building sugars  Dehydration synthesis | fructose | glucose monosaccharides | sucrose (table sugar) disaccharide H2OH2O

AP Biology Polysaccharides  Polymers of sugars  costs little energy to build  easily reversible = release energy  What are they used for?  energy storage  starch (plants)  glycogen (animals)  in liver & muscles  structure  cellulose (plants)  chitin (arthropods & fungi)

AP Biology (a) The structure of the chitin monomer. O CH 2 OH OH H H H NH C CH 3 O H H (b) Chitin forms the exoskeleton of arthropods. This cicada is molting, shedding its old exoskeleton and emerging in adult form. (c) Chitin is used to make a strong and flexible surgical thread that decomposes after the wound or incision heals. OH CHITIN!!!!!!!!!!!!!!

AP Biology Polysaccharides in cells starch (plant) glycogen (animal) energy storage

AP Biology Polysaccharides in cells  As starch is being stored, it undergoes hydrolysis reactions (as needed) to release energy.

AP Biology Polysaccharide diversity  Molecular structure determines function  isomers of glucose  structure determines function… in starchin cellulose

AP Biology Digesting starch vs. cellulose starch easy to digest enzyme cellulose hard to digest only bacteria can digest

AP Biology Starch Cellulose

AP Biology Cellulose  Most abundant organic compound on Earth  herbivores contain a mechanism to digest cellulose  most carnivores do not  that’s why they eat meat to get their energy & nutrients  cellulose = “insoluble fiber”

Regents Biology Cow can digest cellulose well; no need to eat other sugars Gorilla can’t digest cellulose well; must add another sugar source, like fruit to diet

Regents Biology Helpful bacteria  How can herbivores digest cellulose so well?  BACTERIA live in their digestive systems & help digest cellulose-rich (grass) meals

Regents Biology Any Questions??