Chapter 5. Macromolecules

W-H

Chapter 5.

Macromolecules

W-H Based on work by K. Foglia

Macromolecules Smaller organic molecules join together

to form larger molecules macromolecules

4 major classes of macromolecules: carbohydrates lipids proteins nucleic acids

W-H Based on work by K. Foglia

Polymers Long molecules built by linking chain

of repeating smaller units polymers monomers = repeated small units covalent bonds

W-H Based on work by K. Foglia

How to build a polymer Condensation reaction

dehydration synthesis joins monomers by “taking” H2O out

1 monomer provides OH the other monomer provides H together these

form H2O requires energy

& enzymes

W-H Based on work by K. Foglia

How to break down a polymer Hydrolysis

use H2O to break apart monomers reverse of condensation reaction H2O is split into H and OH H & OH group attach where the covalent

bond used to be ex: digestion is

hydrolysis

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Carbohydrates

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So what’s all this talk about carbs?

Atkin’s DietSouth Beach Diet

W-H Based on work by K. Foglia

Carbohydrates Carbohydrates are composed of C, H, O

carbo - hydr - ateCH2O

(CH2O)x C6H12O6

Function: energy energy storage raw materials structural materials

Monomer: sugars ex: sugars & starches

W-H Based on work by K. Foglia

Sugars Most names for sugars end in -ose Classified by number of carbons

6C = hexose (glucose) 5C = pentose (fructose, ribose) 3C = triose (glyceraldehyde)

W-H Based on work by K. Foglia

What functional groups?

carbonyl

ketone

aldehyde

hydroxyl

W-H Based on work by K. Foglia

Sugar structure 5C & 6C sugars form rings in aqueous solutions

in cells!

Carbons are numbered

W-H Based on work by K. Foglia

Numbered carbons

C

CC

C

CC

1'

2'3'

4'

5'6'

O

W-H Based on work by K. Foglia

Simple & complex sugars Monosaccharides

simple 1 monomer sugars glucose

Disaccharides 2 monomers sucrose

Polysaccharides large polymers starch

W-H Based on work by K. Foglia

Building sugars Dehydration synthesis

|glucose

|glucose

glycosidic linkage

monosaccharides disaccharide

|maltose

W-H Based on work by K. Foglia

Building sugars Dehydration synthesis

|fructose

|glucose

glycosidic linkage

monosaccharides disaccharide

|sucrose

structural isomers

W-H Based on work by K. Foglia

Polysaccharides Polymers of sugars

costs little energy to build easily reversible = release energy

Function: energy storage

starch (plants) glycogen (animals)

building materials = structure cellulose (plants) chitin (arthropods & fungi)

W-H Based on work by K. Foglia

Branched vs linear polysaccharides

W-H Based on work by K. Foglia

Polysaccharide diversity Molecular structure determines function

isomers of glucose How does structure influence function…

W-H Based on work by K. Foglia

Digesting starch vs. cellulose

W-H Based on work by K. Foglia

Cellulose Most abundant organic compound

on Earth

W-H Based on work by K. Foglia

Glycemic index Which food will get into your

blood more quickly? apple rice cakes corn flakes bagel peanut M&M

W-H Based on work by K. Foglia

Glycemic index Ranking of carbohydrates based on their

immediate effect on blood glucose (blood sugar) levels

Carbohydrate foods that breakdown quickly during digestion have the highest glycemic indices. Their blood sugar response is fast & high.

W-H Based on work by K. Foglia

Glycemic index Which food will get into your

blood more quickly? apple 36 rice cakes 82 corn flakes 84 bagel 72 peanut M&M33

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Let’s build some

Carbohydrates!