CARBOHYDRATES:
WHAT ARE THEY?
CARBOHYDRATES (SUGARS)
• GIVE ENERGY AND STRUCTURE
• MOST ABUNDANT OF THE BIOMOLECULES
STRUCTURE OF CARBOHYDRATES:
• MADE OF CARBON, HYDROGEN, AND OXYGEN. GENERAL
FORMULA: CH2O
• TYPICALLY HAS A 1:2:1 RATIO
• EX. A COMMON SUGAR, GLUCOSE, HAS THE CHEMICAL
FORMULA C6H12O6. IN A CHEMICAL FORMULA, THE 6:12:6
RATIO OF ELEMENTS REDUCES TO 1:2:1
FUNCTION OF CARBOHYDRATES:
Functions
Examples
Primary Energy Source (Quick energy) Glucose, sucrose, fructose,
Very little energy required to
galactose, ribose, deoxyribose
breakdown is reason it’s used first
Energy storage
Starch (plants), Glycogen (animals
– muscles and liver)
Structural
Cellulose (plant fiber), Chitin
(exoskeleton, cell walls in fungi)
Many carbohydrate names end in –ose. Ex. Ribose, Glucose, Sucrose
PRODUCTION
 Produced by
green plants in
chloroplasts
through
photosynthesis
MONOMERS (BUILDING BLOCKS)
• MONOSACCHARIDES
• MONO = ONE
• SACCHARIDE = SUGAR
EXAMPLES:
 MONOSACCHARIDES:
Glucose (C6H12O6) – blood sugar, used for cellular respiration
Fructose - found in fruit
Galactose – found in milk
Deoxyribose - used in DNA (5 Carbon sugar – missing one “O”)
Ribose: Used in RNA (5 Carbon sugar)
PAUSE!
• QUICKWRITE!
• BRAIN DUMP WHAT WE’VE COVERED SO FAR. ARE THINGS
CLEAR? WHAT CONFUSES YOU?
• HOW WILL MONOSACCHARIDES BUILD UP TO
CARBOHYDRATES?
• HOW DO YOU THINK MONOSACCHARIDES AFFECT EVERYDAY
LIFE?
QUICKSHARE!
• DISCUSS WHAT YOU WROTE WITH YOUR PARTNER.
• ARE THERE ANY SIMILARITIES?
• DIFFERENCES?
• BE PREPARED TO SHARE.
REVIEW! HOW ARE POLYMERS PUT TOGETHER?
 Two single sugars are put together – pulling a water
molecule out to build a bond by taking the OH group off
and the hydrogen atom off the other molecule.
 Two molecules bind together through an atom of oxygen.
REVIEW! HOW ARE POLYMERS PUT TOGETHER?
• Dehydration Synthesis – removing H2O = Two sugars join together
DISACCHARIDES:
• DISACCHARIDES (DI = TWO):
a. SUCROSE (C12H22O11) – TABLE SUGAR
(GLUCOSE + FRUCTOSE)
b. LACTOSE – SUGAR FOUND IN MILK
(GLUCOSE + GALACTOSE)
c. MALTOSE – SUGAR FOUND IN GERMINATING GRAIN
(GLUCOSE + GLUCOSE)
REVIEW! HOW ARE POLYMERS TAKEN APART?
Hydrolysis: Hydro (water) lysis (to cut) = cutting with water
PAUSE!
• QUICKWRITE!
• SUMMARIZE WHAT WE’VE TALKED ABOUT SO
FAR. WHAT IS MOST RELEVANT TO EVERYDAY
LIFE? WHAT IS MOST CONFUSING?
QUICKSHARE!
•DISCUSS WHAT YOU WROTE WITH
YOUR PARTNER. ARE THERE ANY
SIMILARITIES? DIFFERENCES?
•BE PREPARED TO SHARE.
POLYSACCHARIDES (POLY = MANY)
• STARCH (STORAGE ROLE) – BENT CHAINS (PLANTS)
• HUNDREDS OF GLUCOSE MOLECULES ARE ATTACHED OVER AND OVER AGAIN.
WHY ARE PLANTS DOING IT? WHY DO PLANTS MAKE THESE LARGE MOLECULES?
- STORE EXCESS SUGARS.
POLYSACCHARIDES (POLY = MANY)
• GLYCOGEN (STORAGE ROLE) – CHAINS ARE BRANCHED (ANIMALS)
• THOUSANDS OF GLUCOSE MOLECULES ARE BROKEN DOWN TO
MONOSACCHARIDES
 REATTACH THEM AGAIN AND STORE AS GLYCOGEN IN
THE LIVER AND OUR MUSCLES.
• WE CAN GET TO THAT STORAGE WHEN WE NEED IT  CHOP UP THOSE
MONOSACCHARIDES IN ORDER TO USE THEM IN OUR CELLS.
POLYSACCHARIDES (POLY = MANY)
• CELLULOSE (STRUCTURAL ROLE - STRAIGHT CHAINS)
• THE STRUCTURE IN PLANTS IS MADE OF CELLULOSE. MAJOR COMPONENT
OF PLANTS’ CELL WALL; COMMONLY KNOWN AS FIBER (ROUGHAGE) –
FORM STRAIGHT CHAINS – PROVIDES RIGIDITY – GIVES “CRUNCH” TO
FRUITS AND VEGETABLES THERE ARE HYDROGEN BONDS BETWEEN THE
POLYSACCHARIDES, WHICH MAKES THEM VERY DURABLE.
POLYSACCHARIDES (POLY = MANY)
• CHITIN (STRUCTURAL ROLE - STRAIGHT CHAINS - LINEAR)
• STRUCTURE IN EXOSKELETON OF ARTHROPODS AND CELL
WALLS OF FUNGI – FORM STRAIGHT CHAINS