2. OH H H HO CH 2 OH H H H OH O Carbohydrates

3. Carbohydrates are composed of C, H, O carbo - hydr - ate CH 2 O (CH 2 O) x C 6 H 12 O 6 Function: Energy storage structural materials Monomer: monosaccharides (simple sugars) sugar sgar

4. Numbered carbons C CC C C C 1' 2'3' 4' 5' 6' O energy stored in C-C bonds

5. Sugars Most names for sugars end in -ose Classified by number of carbons 6C = hexose (glucose) 5C = pentose (ribose) 3C = triose (glyceraldehyde) OH H H HO CH 2 OH H H H OH O Glucose H OH HO O H H H Ribose CH 2 OH Glyceraldehyde H H H H OH O C C C 653

6. Functional groups determine function carbonyl ketone aldehyde carbonyl

7. Simple & complex sugars Monosaccharides simple 1 monomer sugars Glucose, galactose, fructose Disaccharides 2 monomers Sucrose, lactose, maltose Polysaccharides large polymers Starch, Glycogen OH H H HO CH 2 OH H H H OH O Glucose

8. Building sugars Dehydration synthesis | glucose | glucose monosaccharidesdisaccharide | maltose

9. Building sugars Synthesis | fructose | glucose monosaccharides | sucrose (table sugar) disaccharide

10. Polysaccharides Polymers of sugars costs little energy to build easily reversible = release energy Function: energy storage starch (plants) glycogen (animals) structure = building materials cellulose (plants) chitin (arthropods & fungi) peptidoglycan (bacteria)

11. Linear vs. branched polysaccharides starch (plant) glycogen (animal) energy storage

12. Polysaccharide diversity Molecular structure determines function  isomers of glucose  structure determines function… in starchin cellulose

13. Digesting starch vs. cellulose starch easy to digest enzyme cellulose hard to digest

14. 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

15. Helpful bacteria How can cows digest cellulose? bacteria live in their gut & help digest cellulose-rich (grass) meals