1. TOPIC 3.2 Carbohydrates, Lipids and Proteins

2. 3.2.1 Organic and Inorganic Organic Compounds Inorganic Compounds
Produced by living things
All C containing compounds found in living things except hydrogencarbonates (HCO3-), carbonates (CO32-) and oxides of carbon (CO and CO2)
Inorganic Compounds
All other compounds

3. Important Organic Compounds in Living Things (biochemicals)
Molecule
Subcomponents
(precursors or subunits)
Example Molecules
carbohydrates
monosaccharides
monosaccharides: glucose, galactose, fructose
disaccharides: maltose, lactose, sucrose
polysaccharide: starch, glycogen, cellulose
proteins
amino acids
enzymes, antibodies
lipids
fatty acids
triglyceride, phospholipid
nucleic acids
nucleotides
DNA, RNA

4. 3.2.2 Identify Glucose & Ribose from Diagrams
Carbohydrates contain C, H and O in approximately a 1:2:1 ratio
Building blocks = monosaccharides or simple sugars
Types of carbohydrates:
Monosaccharides (one simple sugar molecule)
Disaccharides (two simple sugar molecules covalently bonded together)
Polysaccharides (many simple sugar molecules covalently bonded together

5. Glucose – a monosaccharide
C6H12O6 Hexagon shape with 6 carbon atoms

6. Ribose – a monosaccharide (pentose sugar = 5 carbon atoms)
C5H10O4
Deoxyribose is the sugar
component of DNA
C5H10O5
Ribose is the sugar
component of RNA

7. 3.2.3 Monosaccharide, Disaccharide and Polysaccharide (3 examples of each)
Monosaccharides = glucose, fructose and galactose (all C6H12O6)
Isomers = same chemical formula, but different structural formula
Disaccharides = maltose, sucrose and lactose
Isomers (all C12H22O11)
Polysaccharides = starch, glycogen and cellulose
Plants store glucose as the polysaccharide starch
Animals store glucose as the polysaccharide glycogen

8. 3.2.4 Functions of Carbohydrates in Animals and Plants
Glucose = source of E ; glucose is broken down to produce ATP in cellular respiration
Lactose = sugar found in milk of mammals; source of E
Glycogen = used for short term E storage in the liver and muscles
Plants:
Fructose = very sweet; good source of E (found in fruits)
Sucrose = used to transport and store E
Cellulose = one of the primary components of cell walls

9. 3.2.5 Condensation Reaction (dehydration synthesis)
Two molecules of glucose form maltose plus water
condensation reaction=
a water molecule is
removed as two glucose
combine to form
maltose (also called
dehydration synthesis)
C6H12O6 + C6H12O C12H22O11 + H2O

10. Condensation and Hydrolysis Reactions (cont.)
glucose + glucose maltose + water
glucose + fructose sucrose + water
glucose + galactose lactose + water
this direction ( ) indicates condensation
this direction ( ) indicates hydrolysis
(hydro = water; lysis = splitting)

11. 3.2.2 Identify Fatty Acids from Diagrams
the building blocks of lipids
lipids include triglycerides (glycerol plus three fatty acids), phospholipids and steroids (ex. cholesterol)
triglyceride structure:
condensation reaction
unsaturated fatty acid
saturated fatty acids

12. 3.2.6 Lipids
contain C, H and O atoms, but not in a 1:2:1 ratio like carbohydrates…lipids contain very few O atoms
fats and oils are lipids
fats generally come from animals; they are solid at room T°; contain single bonds and are saturated
oils generally come from plants; they are liquid at room T°; contain 1 or more double bonded carbon atoms and are unsaturated
lipids store twice the energy of carbohydrates
important for insulation, Energy storage and membrane structure

13. 3.2.2 Identify Amino Acids from Diagrams
polypeptides are long chains of amino acids
amino acids are the building blocks of proteins
20 different amino acids all have similar structure:
central C atom has four groups attached to it:
amine group - NH2
carboxyl group - COOH
a hydrogen atom - H
the “R” group which is different in different amino acids

14. Generalized Amino Acid Structure

15. Amino Acids Form Chains Condensation Reactions
polypeptide chains are formed through condensation reactions (dehydration synthesis) at ribosomes
water molecule removed