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

H2O

HO

HO H

H HHO

How to build a polymer Synthesis http://nutrition.jbpub.com/resources/animations.cfm?id=6

joins monomers by “taking” H2O out one monomer donates OH–

other monomer donates H+ together these form H2O

requires energy & enzymes

enzymeDehydration synthesis

Condensation reaction

AP Biology

H2O

HO H

HO H HO H

How to break down a polymer

Digestion http://nutrition.jbpub.com/resources/animations.cfm?id=7&debug=0

use H2O to breakdown polymers reverse of dehydration synthesis cleave off one monomer at a time

H2O 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

CH2O

(CH2O)x C6H12O6

Function: fast energy u energy storage raw materials ustructural materials

Monomer: sugars

ex: sugars, starches, cellulose

sugar sugar sugar sugar sugar sugar sugarsugar

C6H12O6(CH2O)x

AP Biology

Functional groups determine function

carbonyl

ketone

aldehyde

carbonyl

AP Biology

Sugar structure5C & 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

OH

H

H

HO

CH2OH

H

H

H

OH

O

Glucose

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Building sugars Dehydration synthesis

|glucose

|glucose

monosaccharides disaccharide

|maltose

H2O

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Building sugars Dehydration synthesis

|fructose

|glucose

monosaccharides

|sucrose

(table sugar)

disaccharide

H2O

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

CH2OH

OHH

H OH

H

NH

C

CH3

O

H

H

(b) Chitin forms the exoskeleton of arthropods. This cicada is molting, shedding its old exoskeleton and emergingin adult form.

(c) Chitin is used to make a strong and flexible surgical

thread that decomposes after the wound or incision heals.

OH

CHITIN!!!!!!!!!!!!!!CHITIN!!!!!!!!!!!!!!

AP Biology

Polysaccharides in cells

starch(plant)

glycogen(animal)

energystorag

e

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 starch in cellulose

AP Biology

Digesting starch vs. cellulose

starcheasy todigest enzyme

enzyme

cellulosehard todigest

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

Cowcan digest cellulose well; no need to eat other sugars

Gorillacan’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 2007-2008

Any Questions??