Download glucose + fructose

 Biomolecules are organic molecules produced by living organisms
which consists mainly of the following elements:
 These elements are non-metals which combine in various ways to
form biomolecules through a covalent type of bonding.
 A wide range of biomolecules exist, including large molecules known
as macromolecules and small molecules known as micromolecules.
 Biomolecules are categorized into four classes.
They are polymers of
repeating units of smaller
molecules called
monomers.
Biomolecule
Element Content
Example
Building Block
Carbohydrate
Carbon, Hydrogen,
Oxygen
polysaccharide
monosaccharide
Protein
Carbon, Hydrogen,
Oxygen, Nitrogen, Sulfur
polypeptide
amino acid
Lipid
Carbon, Hydrogen,
Oxygen
triglyceride
glycerol and fatty
acid
Nucleic Acid
Carbon, Hydrogen,
Oxygen, Nitrogen,
Phosphorous
DNA/RNA
nucleotide
Through a covalent type of
bonding, these monomers
create various forms of each
organic molecule.
Physiological
functions
rely on
energy
can be
provided by
Carbohydrates
are classified as
Monosaccharides
Disaccharides
Polysaccharides
composed of
Carbon
Hydrogen
Oxygen
Lipids
are classified as
Triglycerides (fats & oils)
Phospolipids
Steroids (Cholesterol)
Waxes
 The most abundant class of biomolecules
 A chief source of energy of almost all living organisms
 Originated from the French word hydrate de carbone, which means
“hydrates of carbon”
 Sometimes called saccharides, from the Greek word sakcharon,
meaning “sugar”
 The suffix –ose is used to denote the name of a saccharide
 Food that are high in carbohydrates include:
FRUITS
SWEETS
RICE
BREAD AND PASTA
BEANS AND POTATOES
CEREAL
 Contain the elements carbon, hydrogen and nitrogen
 They have an C:H:O ratio of 1:2:1 based on their general formula
Cn(H2O)n
 Carbohydrates include sugars, starches, cellulose, and many other
compounds in organisms
 They are either formed from or decomposed into other carbohydrate
forms through the physiological processes in plants and animals
 Example: THROUGH THE PROCESS OF PHOTOSYNTHESIS  CO2 and H2O to
form the sugar, glucose.
 Primary functions of carbohydrates in living
organisms:
 Substrate for respiration
 Source of energy
 Intermediate substances in respiration
(glyceraldehydes)
 Energy storage (starch and glycogen)
 Structure (chitin in arthropod exoskeleton and
fungal walls)
 Transport (sucrose transported in the phloem of a
plant)
 Recognition of molecules that pass through the cell
membrane
CHAIN FORM
GLUCOSE
RING FORM
MONOSACCHARIDES
 Simplest carbohydrates
 Most basic unit of a carbohydrate
 Also know as simple sugars
 Only sugars that can be absorbed
and utilized by the body
 At room temperature: crystalline
white solids
 All carbon atoms have –OH
groups in their molecular
structure except one which has an
aldehyde (-CHO) or ketone (-CO)
group
 Polar and very soluble in water
Name of
monosaccha
ride
Derivation of Name
Source
Greek word “Gleukos” –
sweet wine
Grape sugar, blood
sugar, dextrose
Galactose
Greek word “Galact” –
milk
Component of
lactose in milk
Fructose
Latin word “Fructus” –
fruit
Fruits, honey,
sweetest sugar
Glucose
(also known as levulose)
Ring
Formula
 ALDOSE – if it contains an aldehyde group (-CHO)
 KETOSE – if it contains a ketone group (-CO)
 NUMBER OF CARBON ATOM (Ex. C3 – triose; C4-tetrose; C5-pentose;
C6-hexose; C7- heptose; C8-octose; C9-nonose)
 Simplest monosaccharides: triose glyceraldehyde &
dihydroxyacetone
ISOMERS
DISACCHARIDES
 Made up of two monosaccharide units
 Joined by a GLYCOSIDIC BOND (type of covalent bond that links a carbohydrate unit to
another)
 Has a molecular formula of C12H22O11
 Cannot be directly utilized by the body unless broken down into monosaccharides
+
Condensation & hydrolysis of SUCROSE
H 2O
SUCRALOSE is an artificial sweetener made from sugar but
contains NO CALORIES.
 Derived from Cane sugar (sucrose)
 Three hydroxyl groups are replaced with CHLORINE atoms.
 Chemically inert and is NOT broken down to its component monosaccharides,
glucose & fructose.
 NOT METABOLIZED; it yields NO CALORIES and passes through and out of the
body unchanged.
Name of
Disaccharide
Derivation of
Name
Source
SUCROSE
French word
“Sucre” - sugar
Table sugar,
cane sugar,
beet sugar
Latin word
“Lact” - milk
milk
Old
English“mealt”
- malt
Germinating
grains;
Used in
making BEER
(glucose +
fructose)
LACTOSE
(glucose +
galactose)
MALTOSE
(glucose +
glucose)
Ring
Formula
POLYSACCHARIDES
 Composed of a long chain of monosaccharide units (10 or more)
 Also called POLYMERS (“poly”- many; “mers” – monomers)
 High molecular mass
 Glucose is the repeating monomer unit
 Only differ in the number of glucose units, the extent of branching & the
position of the glycosidic bonds
 Two types:
1) Homopolysaccharides (formed by the same type of monosaccharides)
Ex. Starch, glycogen, cellulose
2) Heteropolysaccharides (formed by different type of monosaccharides)
Ex. glycosamines, peptidoglycans
Name of
Polysaccharide
Source
STARCH
(Dutch word:
“Sterken”)
• Stored form of
glucose in PLANTS
• Cereals (wheat; rice)
• Tubers (Potatoes)
CELLULOSE
• Rigid cell walss in
plants
(French word “cellule”
– small cell)
GLYCOGEN
(no word origin)
• Stored in the form of
glucose in ANIMALS
& HUMANS (liver &
muscles)
Ring
Formula
 GLYCOSIDIC BONDS (STARCH & CELLULOSE)
 GLYCOSIDIC BONDS (GLYCOGEN)
 Thousands of glucose  cellulose molecule (which constitutes the
structural framework of plants)
 Glucose may fuse = STARCH (seeds and serve as food for a growing
plant)
 Animals and humans  eat cellulose or starch  broken down to
glucose units  carried by the blood to the liver  recombined to
form glycogen (animal starch)  stored
 If the body needs energy  glycogen is broken down to glucose
then transferred to the tissues were it is oxidized to carbon dioxide
and water.
 Some of the glucose  fats
 Some react with nitrogen-containing compounds  amino acids
(which in turn are combined to manufacture proteins)
TEST FOR REDUCING SUGARS
 Benedict’s solution
 Fehling’s solution
 Tollen’s reagent
Precipitation
and
change in color
Iodine-potassium iodide test
 used to detect the presence of
STARCH (blue-black color)