BIOLOGICAL MOLECULES
4 BIOMOLECULES
UNFOLDING THE STRUCTURES AND
FUNCTIONS OF BIOLOGICAL MOLECULES
AFTER GOING THROUGH THIS LESSON, YOU ARE
EXPECTED TO:
• DEFINE BIOLOGICAL MOLECULES;
• IDENTIFY THE ROLE OF EACH BIOLOGICAL
MOLECULE IN SPECIFIC METABOLIC PROCESSES;
• DIFFERENTIATE EACH BIOLOGICAL MOLECULES
ACCORDING TO THEIR STRUCTURE AND FUNCTION
BIOLOGICAL MACROMOLECULES
•THERE ARE FOUR MAJOR CLASSES OF BIOLOGICAL
MACROMOLECULES
(CARBOHYDRATES, LIPIDS, PROTEINS AND NUCLEIC ACIDS)
• THEY ARE ORGANIC, MEANING THEY CONTAIN CARBON. IN
ADDITION, THEY MAY CONTAIN HYDROGEN, OXYGEN,
NITROGEN AND ADDITIONAL MINOR ELEMENTS
BIOLOGICAL MACROMOLECULES
MACROMOLECULES ARE POLYMERS,
BUILT FROM MONOMERS.
• MACROMOLECULES ARE FORMED BY SHARING ELECTRONS
AND FORM COVALENT BONDS.
• IT IS FACILITATED BY THE FOLLOWING PROCESSES
A. DEHYDRATION SYNTHESIS
B. HYDROLYSIS
DEHYDRATION
SYNTHESIS
• ALSO CALLED
CONDENSATION REACTION
• REACTION THAT OCCURS
TO BUILD POLYMERS
• WATER MOLECULE IS LOST
AS A BY-PRODUCT
• REQUIRES ENERGY INPUT,
ENZYME.
HYDROLYSIS
• POLYMERS ARE BROKEN
DOWN INTO MONOMERS
• MEANS “TO SPLIT WATER”
• A REACTION IN WHICH A
WATER MOLECULE IS
USED DURING THE
BREAKDOWN.
• RELEASES ENERGY
• ACCELERATED BY ENZYME
ENZYME
AN ORGANIC MOLECULE THAT SPEEDS UP A
CHEMICAL REACTION BY LOWERING THE
AMOUNT OF ENERGY REQUIRED TO START A
CHEMICAL REACTION
Components in
Enzyme Activity:
• Substrate
• Active site
• Enzyme
• Product
Factors that affect rate of
enzyme activity:
• pH level
• temperature
Activity Time!
EFFECTS OF pH AND TEMPERATURE ON
ENZYME ACTION
Using the data in the chart, plot a graph showing the rate of enzyme action for the
enzymes Pepsin and Trypsin at varying pH.
pH
Rate of
Pepsin
Action
Rate of
Trypsin
Action
1
1
0
2
3
0
3
7
0
4
3
0
5
1
1
6
0
3
7
0
7
8
0
9
9
0
7
10
0
3
11
0
1
1
12
0
0
0
13
0
0
14
0
0
pH-Enzyme Activity Rate
10
9
R
a
t
e
8
7
6
5
4
3
2
1
2
3
4
5
6
7
8
9
10
pH
11
12
13
14
Using the data in the chart, plot a graph showing the rate of enzyme action at different
temperature.
Temp
0C
Reaction
rate
10
1.0
15
1.5
20
2.5
25
3.5
30
5.5
35
7.5
40
9.5
45
8.5
50
7.0
55
4.0
60
0.0
Temperature-Enzyme Activity Rate
R
a
t
e
10
9.5
9
8.5
8
7.5
7
6.5
6
5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
5
10 15 20 25 30 35 40 45 50 55 60 65 70
Temperature
Analysis:
1. At what pH is trypsin most
effective? How about pepsin?
2. What is the best temperature for
this enzyme to work?
CARBOHYDRATES
• THEY ARE ORGANIC COMPOUNDS MADE UP OF CARBON,
HYDROGEN AND OXYGEN.
• CARBOHYDRATES CAN BE REPRESENTED BY THE
STOICHIOMETRIC FORMULA (CH2O).
• CARBOHYDRATES INCLUDE SUGARS AND THE POLYMERS OF
SUGARS
• THE SIMPLEST CARBOHYDRATES ARE MONOSACCHARIDES, OR
SIMPLE SUGARS
• CARBOHYDRATE MACROMOLECULES ARE POLYSACCHARIDES,
POLYMERS COMPOSED OF MANY SUGAR BUILDING BLOCKS
CARBOHYDRATES
• TYPES OF CARBOHYDRATES
1. MONOSACCHARIDES
2. OLIGOSACCHARIDES
3. POLYSACCHARIDES
MONOSACCHARIDES
• Monosaccharides (mono- = “one”; sacchar- = “sweet”) are
simple sugars
• Most monosaccharide names end with the suffix -ose. If the
sugar has an aldehyde group (the functional group with the
structure R-CHO), it is an ALDOSE, and if it has a ketone group
(the functional group with the structure RC(=O)R'), it is a
KETOSE.
• Depending on the number of carbons in the sugar, they can be
trioses (three carbons), pentoses (five carbons), and/or
hexoses (six carbons).
ALDOSE
KETOSE
6 CARBONS
6 CARBONS
- OSE
- OSE
ALDOHEXOSE
KETOHEXOSE
MONOSACCHARIDES
• GLUCOSE (C6H12O6) IS THE MOST COMMON
MONOSACCHARIDE.
EXAMPLES:
• GLUCOSE – A 6 CARBON ALDOSE THAT IS THE PRODUCT OF
PHOTOSYNTHESIS AND THE SUBSTRATE FOR RESPIRATION
THAT PROVIDES ENERGY FOR CELLULAR ACTIVITIES.
• FRUCTOSE – A CARBON KETOSE THAT IS FOUND IN MANY
PLANTS AND IS OFTEN BONDED TO GLUCOSE.
• GALACTOSE – A 5 CARBON ALDOSE THAT FORMS PART OF
THE NUCLEIC ACIDS.
OLIGOSACCHARIDES
• OLIGO MEANS FEW
• CARBOHYDRATE CHAINS CONTAINING 2–10 SUGAR UNITS
COVALENTLY BONDED BY A GLYCOSIDIC LINKAGE.
• FUNCTIONS AS ENERGY SOURCE, SWEETENER AND
DIETARY COMPONENT.
• TYPES:
DISSACCHARIDES- 2 UNITS OF SUGAR
TRISACCHARIDES- 3 UNITS OF SUGAR
TETRASACCHARIDES- 4 UNITS OF SUGAR…
OLIGOSACCHARIDES
EXAMPLES:
• MALTOSE (GLUCOSE + GLUCOSE) – MALT SUGAR OFTEN FOUND IN
SPROUTING GRAINS, MALT-BASED ENERGY DRINKS OR BEER.
• SUCROSE (GLUCOSE + FRUCTOSE) – FOUND IN TABLE SUGAR
PROCESSED FROM SUGAR CANE, SWEET FRUITS AND STORAGE
ROOT LIKE CARROTS.
• LACTOSE (GLUCOSE + GALACTOSE) – MILK SUGAR THAT IS A
SOURCE OF ENERGY FOR INFANTS; AN ENZYME CALLED LACTASE IS
REQUIRED TO DIGEST IT.
POLYSACCHARIDES
EXAMPLES:
 STORAGE POLYSACCHARIDES ARE LARGE MOLECULES RETAINED IN
THE CELL AND ARE INSOLUBLE IN WATER.
1. STARCH – AMYLASE IS UNBRANCHED STARCH FORMING A HELICAL
STRUCTURE WHILE AMYLOPECTIN IS BRANCHED STARCH, THESE
ARE PRESENT IN PLANTS PARTS LIKE POTATO TUBERS, CORN AND
RICE AND SERVE AS MAJOR SOURCES OF ENERGY.
2. GLYCOGEN – FOUND IN ANIMALS AND FUNGI; OFTEN FOUND IN
LIVER CELLS AND MUSCLE CELLS.
POLYSACCHARIDES
 STRUCTURAL POLYSACCHARIDES
1. CELLULOSE – TOUGH SHEET LIKE STRUCTURES THAT MAKE UP
PLANT AND ALGAL CELL WALLS THAT MAY BE PROCESSED TO
FORM PAPER AND PAPER-BASED PRODUCTS.
2. CHITIN – USED FOR STRUCTURAL SUPPORT IN THE WALLS OF
FUNGI AND IN EXTERNAL SKELETONS OF ARTHROPODS.
3. PEPTIDOGLYCAN – USED FOR STRUCTURAL SUPPORT IN
BACTERIAL CELL WALLS.
Review of Carbs
1. The process involved in building up glucose and fructose to form
sucrose.
2. Monomer of carbohydrates found in animals.
3. A disaccharide form when 2 molecules of glucose undergo
dehydration synthesis.
4. An organic compound composed of carbon, hydrogen and oxygen.
5. An enzyme necessary to break down lactose into glucose and
galactose.
6. 2 Important polysaccharides found in plants and animals which
function as storage.
7. --8. 2 important polysaccharides found in plants and bacteria that
forms as structural components.
9. --10. Name the Monosaccharide
1. The process involved in building up glucose and fructose to form
sucrose. DEHYDRATION SYNTHESIS
2. Monomer of carbohydrates found in animals. GALACTOSE
3. A disaccharide form when 2 molecules of glucose undergo
dehydration synthesis. MALTOSE
4. An organic compound composed of carbon, hydrogen and oxygen. CARBOHYDRATES
5. An enzyme necessary to break down lactose into glucose and
galactose. LACTASE
6. 2 Important polysaccharides found in plants and animals which
function as storage. STARCH
7. --GLYCOGEN
8. 2 important polysaccharides found in plants and bacteria that
forms as structural components. CELLULOSE
9. --PEPTIDOGLYCANS
10. Name the Monosaccharide
ALDOTETROSE
LIPIDS
• LIPIDS ARE A CLASS OF LARGE BIOMOLECULES THAT ARE NOT
FORMED THROUGH POLYMERIZATION.
• THEY MAY HAVE SOME OXYGEN ATOMS IN THEIR STRUCTURE
BUT THE BULK IS COMPOSED OF ABUNDANT NON-POLAR
CARBON-HYDROGEN BONDS.
• THEY PLAY IMPORTANT ROLES IN PLASMA MEMBRANE
STRUCTURE AND SERVE AS PRECURSORS FOR IMPORTANT
REPRODUCTIVE HORMONES.
FATS
(TRIACYLGLYCEROLS OR
TRIGLYCERIDES)
• ENERGY STORAGE, CUSHIONING
OF VITAL ORGANS (ADIPOSE
TISSUE) AND INSULATION
• FATS ARE CONSTRUCTED FROM
TWO TYPES OF SMALLER
MOLECULES: GLYCEROL AND
FATTY ACIDS
• GLYCEROL IS A THREE-CARBON
ALCOHOL WITH A HYDROXYL
GROUP ATTACHED TO EACH
CARBON
• A FATTY ACID CONSISTS OF A
CARBOXYL GROUP ATTACHED
TO A LONG CARBON SKELETON
FATS
EXAMPLES:
• SATURATED FAT – ANIMAL PRODUCTS SUCH AS BUTTER AND
LARD HAVE A LOT OF SATURATED FATTY ACIDS.
• UNSATURATED FATS – PLANT AND FISH OILS HAVE
UNSATURATED FATTY ACIDS.
• TRANS FAT – MAY BE PRODUCED ARTIFICIALLY THROUGH THE
PROCESS OF HYDROGENATION.
PHOSPHOLIPIDS
• MAJOR COMPONENT OF CELL MEMBRANE MADE OF GLYCEROL,
FATTYACIDS AND PHOSPATE GROUP.
• PHOSPHATE GROUP IS HYDROPHILIC AND IS CALLED THE ‘HEAD’ OF
THE MOLECULE.
• FATTY ACIDS ARE HYDROPHOBIC AND FORM THE ‘TAILS’ OF THE
MOLECULE.
STEROIDS AND STEROLS
•
•
•
•
REGULATE FLUIDITY OF CELL MEMBRANE.
BASE OF SEX HORMONES.
EMULSIFICATION OF FATS DURING DIGESTION.
CHOLESTEROL FOUND IN CELL MEMBRANE REGULATES THE RIGIDITY OF
THE CELL MEMBRANE AND ARE THE BASE MATERIAL FOR THE
PRODUCTION OF SEX HORMONES LIKE ESTRADIOL AND
PROGESTERONE.
WAXES
• SIMPLE LIPIDS CONSISTS OF LONG CHAIN ALCOHOL AND A FATTY
ACID JOINED BY ESTHER.
• THEY FOUND AS COATING OF STEM AND LEAVES TO PREVENT
EXCESSIVE LOSS OF WATER IN PLANTS.
• IN INSECTS, COVER BODY SURFACES TO RESTRICT MOVEMENT OF
WATER ACROSS THE CUTICLE TO PREVENT THE BODY FROM DRYING.
PROTEINS
• PROTEINS ARE ONE OF THE MOST ABUNDANT ORGANIC
MOLECULES IN LIVING SYSTEMS AND HAVE THE MOST DIVERSE
RANGE OF FUNCTIONS OF ALL MACROMOLECULES.
• THEY MAY BE STRUCTURAL, REGULATORY, CONTRACTILE OR
PROTECTIVE; THEY MAY SERVE IN TRANSPORT, STORAGE OR
MEMBRANES; THEY MAY BE TOXINS OR ENZYMES.
• AMINO ACIDS ARE THE MONOMERS THAT MAKE UP PROTEINS.
POLYPEPTIDES – polymer of protein
TYPES AND FUNCTIONS OF PROTEINS
NUCLEIC ACID
• NATURALLY OCCURRING CHEMICAL
COMPOUND THAT IS CAPABLE OF
BEING BROKEN DOWN TO YIELD
PHOSPHORIC ACID, SUGARS, AND A
MIXTURE OF ORGANIC BASES
(PURINES AND PYRIMIDINES).
• NUCLEIC ACIDS ARE
POLYNUCLEOTIDES, EACH NUCLEIC
ACID CONTAINS FOUR OF FIVE
POSSIBLE NITROGEN-CONTAINING
BASES:
ADENINE (A),
GUANINE (G),
CYTOSINE (C),
THYMINE (T),
URACIL (U).
A. Identify each as Carbohydrates, protein or lipid.
1.Starch
2.Cholesterol
3.Steroid
4.Glycogen
5.Enzyme
6.Saturated fat
7.Polypeptide chain
8.Glucose
9. Polysaccharide
10. Phospholipid
11. Glycerol
12. Monosaccharide
13. Cellulose
14. Amino acid
15. Unsaturated fatty acid
B. Match each molecule
with its components.
COLUMN A
1. Amino acid monomer
2.Fatty acids, carbon rings
3.Glucose, Fructose
4.Glucose monomers
5. Glycerol, fatty acids
6.Glycerol, fatty acids, phosphates
7. Nucleotide monomers
8. Sugar, phosphate and nitrogen
bases
COLUMN B
a.
b.
c.
d.
e.
f.
g.
h.
i.
Cellulose
Fat
Nucleotide
Nucleic acid
Phospholipid
Protein
Sucrose
Wax
Glucose
A. Identify each as Carbohydrates, protein or lipid.
1.Starch
2.Cholesterol
3.Steroid
4.Glycogen
5.Enzyme
6.Saturated fat
7.Polypeptide chain
8.Glucose
9. Polysaccharide
10. Phospholipid
11. Glycerol
12. Monosaccharide
13. Cellulose
14. Amino acid
15. Unsaturated fatty acid
B. Match each molecule with its components.
COLUMN A
1. Amino acid
2.Fatty acids, carbon rings
3.Glucose, Fructose
4.Carbohydrates monomer
5. Glycerol, fatty acids
6.Glycerol, fatty acids, phosphates
7. Nucleic acid monomers
8. Sugar, phosphate and nitrogen
bases
COLUMN B
a.
b.
c.
d.
e.
f.
g.
h.
i.
Cellulose
Fat
Nucleotide
Nucleic acid
Phospholipid
Protein monomer
Sucrose
Steroid
Glucose