Lipids

Review of the previous lecture…

• Emergent Properties.

• Elements &

Compounds.

• Valence Electrons &

Chemical Bonds.

• Electronegativity and

Polarity.

• Functional Groups

• Water: cohesion,

temperature

moderation, floating

ice, universal solvent.

• Acids & Bases: proton

donors and proton

acceptors.

• Carbon: Tetravalent,

shape, isomers,

functional groups.

Chapter 5: Structure and Function of Large

Biomolecules

1

Key Concepts For Chapter 5

• Concept 1: Macromolecules are polymers, built from monomers.

• Concept 2: Carbohydrates serve as fuel and building material.

• Concept 3: Lipids are a diverse group of hydrophobic molecules.

• Concept 4: Proteins have many structures, resulting in a wide

range of functions.

• Concept 5: Nucleic acids store and transmit hereditary

information.

Common Themes in Biological Molecules

• All living things are made up of only four classes

of large biological molecules: carbohydrates,

lipids, proteins, and nucleic acids

–

–

–

–

Carbohydrates

Lipids

Proteins

Nucleic acids

• Macromolecules are large molecules composed

of thousands of covalently connected small

organic molecules

Molecular structure and function are inseparable

for creating diversity between organisms

2

Concept 1: Macromolecules are polymers, built

from monomers

• A polymer is a long molecule consisting of

many similar building blocks

• These small building-block molecules are

called monomers

• Three of the four classes of life’s organic

molecules are polymers:

– Carbohydrates (polymers of simple sugars)

– Proteins

(polymers of amino acids)

– Nucleic acids (polymers of nucleotide bases)

The Synthesis and

Breakdown of

Polymers

• Dehydration

reactions link

monomers & release

a water molecules

HO

2

3

H

Short polymer

HO

HO

2

1

H

Unlinked monomer

Dehydration removes a water

molecule, forming a new bond

3

H2O

4

H

4

H

Longer...