Essential Question:

What types of molecules are in the

body?

Macromolecules

The food you eat, the silk a spider uses to make a web, the muscles in your body – all of these structures are made of macromolecules.

Macromolecule is the term that biologists use for

large molecules. There are four types of

macromolecules that are important in biology: carbohydrates, lipids,

proteins, and nucleic acids.

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Macromolecules

• Large organic molecules.• Also called POLYMERS.• Made up of smaller “building blocks” called

MONOMERS.• Examples:

1. Carbohydrates2. Lipids3. Proteins4. Nucleic acids (DNA and RNA)

Carbohydrates

Carbohydrates are a source of energy in our diet. When we eat foods that contain carbohydrates, the energy in them is changed in our cells to a form that our bodies can use. Carbohydrates also form building materials like the chitin that covers the surface of insects and cellulose that makes up plant cell walls.

Carbohydrates are the group that includes simple

sugars and more complex molecules made up of lots of

sugars bonded together.

A carbohydrate made of two sugars is called a disaccharide. An example of this is sucrose, which is table sugar like you may put on your cereal or use to make cookies.

Starch is an example of a complex

carbohydrate made of many linked sugars. Plants often store

carbohydrates in the form of starch. Eating potatoes or grains is the main source of

starch for humans.

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Carbohydrates• Small sugar

molecules to large sugar molecules.

• Examples:A. monosaccharideB. disaccharideC. polysaccharide

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CarbohydratesMonosaccharide: one sugar unit(from Greek: single, sacchar: sugar) are the most

basic units of biologically important carbohydrates. They are the simplest form of sugar and are usually colorless, water-soluble, crystalline solids. Some monosaccharides have a sweet taste.

Examples:glucose (C6H12O6)

deoxyriboseriboseFructoseGalactose

glucose

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CarbohydratesDisaccharide: two sugar unitA disaccharide is the carbohydrate formed when two

monosaccharides undergo a condensation reaction which involves the elimination of a small molecule, such as water, from the functional groups only. Like monosaccharides, disaccharides also dissolve in water, taste sweet and are called sugars.

Examples: – Sucrose (glucose+fructose)– Lactose (glucose+galactose)–Maltose (glucose+glucose)

glucoseglucose

Fructose is a naturally occurring sweetener found in fruit.In diabetics who have adequate insulin available, fructosecauses a slower rise in blood glucose levels than other simple sugars.

Maltose is a disaccharide with a molecular weight identical to sucrose, but it is only 30% as sweet.

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Carbohydrates

Polysaccharide: many sugar unitsExamples: starch (bread, potatoes)

glycogen (beef muscle)cellulose (lettuce,

corn)glucoseglucose

glucoseglucose

glucoseglucose

glucoseglucose

cellulose

Carbohydrate The empirical or

simplest formula of any carbohydrate is (CH2O)n. This formula looks like carbon water just as carbohydrate suggests hydrated or watered carbon. The formula tells us that all carbohydrates are made of carbon, hydrogen, and oxygen atoms in a 1:2:1 ratio.

Question:

How Are Macromolecules

Formed?

Answer: Dehydration Synthesis

• Also called “condensation reaction”

• Forms polymers by combining monomers by “removing water”.

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HO H

HO HO HH

H2O

Question:

How are Macromolecules

separated or digested?

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Answer: Hydrolysis

• Separates monomers by “adding water”

HO HO HH

HO H

H2O

Belgian Undertakers Want to Dissolve & Flush Dead Into Sewers

Photo: Corbis A group of undertakers in Belgium are proposing a more ecological (but perhaps creepier) alternative to cremation: they hope to dissolve corpses in a caustic solution and flush the resulting liquid and ashes down the drain, which will be recycled at water treatment plants. They contend that the process - known as chemical hydrolysis or resomation - would use less energy than a crematorium and emit no carbon emissions. ...