The Molecules of Life

Day 1 - Carbohydrates

MOLECULES OF LIFE

• organic molecules

– Are molecules containing carbon

– Macromolecules (“large molecules)• made of long chains of carbon compounds• building blocks called monomers, I.e. “single

units”• monomers may be bonded together into

polymers, i.e.“many units”

CARBOHYDRATES• means “hydrated carbon”, i.e. carbon + water

– general formula = CH2O

– Made up of C,H and O

– simple carbohydrates are monomers• called monosaccharides, or sugars

– 6 carbon monosaccharides (C6H12O6)• called “hexoses”• glucose, fructose, galactose

– 5 carbon monosaccharides (C5H10O5)• ribose

• deoxyribose

Remember Ribose and Deoxyribose Sugars from DNA?

Glucose

Fructose

• May look 5-sided, but it has 6-Carbons, so it is a hexose sugar

Galactose

• It may look a lot like glucose, but there are differences.

Glucose vs. Galactose

• Inquiring minds want to know ...

Making Disaccarides

• When two monomers come together and pair up, you have a disaccaride.

• Famous disaccarides include1. glucose + glucose = maltose

2. glucose + fructose = sucrose

3. glucose + galactose = lactose

Here’s a brief animation of condensation synthesis also known as dehydration synthesis because WATER IS LOST!

Maltose - A Second Look

Lactose

COMPLEX CARBOHYDRATES ARE CALLEDPOLYSACCARIDES

1. Starch = Plant Polysaccharides- Plants stitch glucose together to form long chains of

starch as stored energy

- Starch tends to form single chains, but doesn’t branch nearly as much as glycogen

2. Glycogen = Animal Polysaccharides– polymer of glucose

– branched chain

– animals• stored in muscles and liver

Starch – a polysaccharide

COMPLEX CARBOHYDRATES…(cont’d)

Cellulose – plants– dietary fiber– straight chain glucose– provides structural support in plants– Note the diagonal links at sharp angles between

glucose molecules.

Consider Cellulose vs. Starch