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Macromolecules

Introduction to the building blocks of life

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The Molecules of Life

• Organization– The next level

Atom

molecule

macromolecule

Macromolecules Large molecules are called macromolecules

The macromolecules are composed of submits called MONOMERS.

A POLYMER is composed of many monomers.

CARBOHYDRATES

LIPIDS

PROTEINS

NUCLEIC ACIDS

4 Classes of Biological Macromolecules

CARBOHYDRATESCARBOHYDRATESMonomer is monosaccharide Monosaccharides are the simple

sugars• They contain C, H and O in a 1:2:1 ratio

and may be represented by the general formula CH2O

glucose fructose

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FunctionFunction1. Fuel (energy)

2. Building material (cellular structure)

Complex CarbohydratesComplex Carbohydrates Glycogen (animals) Starch (plants) are energy

storing Cellulose is in plant cells Chitin is the major component

in the exoskeleton of arthropods

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LIPIDSLIPIDS• Hydrophobic molecules

– fats and oils– waxes – sterols

Monomer is the fatty acidStructure is mostly C and H

Fig. 3.8a, p. 40stearic acid oleic acid linolenic acid

Hydrophilichead

WATER

WATER

Hydrophobictail

Figure 5.14

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FUNCTIONFUNCTION– Energy Storage– Fats store twice as many calories as

carbohydrates– Protection of vital organs and insulation– Fat is stored in adipose cells.

Steroids- differ from other lipids in structure but are classified as a lipid because they are insoluble in water

PROTEINSPROTEINS• Many structures, resulting in a wide range of

functions• Amino acids are the building blocks of

proteins.• Needed for

• Structural support and movement (bone, cartilage, muscle)

• Storage/transport molecules (hemoglobin)• Hormones (insulin-sugar breakdown)• Enzymes (control of cellular reactions)

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NUCLEIC ACIDSNUCLEIC ACIDS• Store and transmit hereditary information• Nucleotides are the monomers that make

– DNA – RNA – ATP