2. Learning Objectives:
Categorize the biological molecules according to
their structure and function
Explain the role of each biological molecule in
specific metabolic processes
3. Overview:
Definition of Biological Molecules
Classification of Biological Molecules
Structure and functions of Biological Molecules
4. Biological Molecules
Biomolecules are essential
molecules for all living organisms
Have unique characteristics and
properties that show how they
contribute to the structure and
function of the cells and how
essential they are in maintaining
life
5. Elements
The simplest form of a substance
found in the body such as C, H, O, N
Compounds
Made up of two or more elements that
are chemically joined together
Inorganic Compounds
Water, Acid, Bases, Salt, Carbon
Dioxide
Organic Compounds
Carbohydrates, Lipids, Proteins,
Nucleic Acids
6. Element
Simplest form of a substance
Cannot be broken down into more simpler form
25 out of the natural elements are essential to
life
98 – 99% of the body is composed of seven
major elements namely C, H, O, N, P, Ca, S
7. Symbol Name Functions
C Carbon
Makes up 18% of the
mass of the human
body
Main component of
organic compounds
H Hydrogen
10% of human body
mass
Essential in energy
production
O Oxygen
61-65% of total
human body mass
Used for cellular
respiration
8. Symbol Name Functions
N Nitrogen
Makes up 3% of
human body mass
Key element of protein
and nucleic acid
P Phosphorus
1.2 – 1.5% of human
body mass
Important for bone
structure
Major component of
nucleic acid
S Sulfur
0.20 – 0.25% of
human body mass
Important components
of proteins
9. Symbol Name Functions
Ca Calcium
1.5% of human body
mass
Gives skeletal system
its rigidity and strength
Found in bones and
teeth
Important for muscle
functions
Si, Cl, Mg, Cu, Zn Minerals
Other elements found
in the body in little
amounts
Essential for growth
and maintenance of
the body
10. Symbol Name Functions
Fe & I Trace Elements
Elements that are
indispensable to life
but is required in
minute amounts
11. Compounds
A substance composed of two or more
elements that are chemically bonded together
Can be classified into inorganic or organic
compounds
Example: H2O, NaCl
12. Atomic Bonding
Atomic Bond Description
Covalent Bond
Sharing of a pair of valence
electrons by two atoms
Represents sharing of electron
Done to satisfy the octet rule
Ionic Bond
Attraction between oppositely
charged atoms (CATIONS,
ANIONS)
Compounds formed from ionic
bonds are called ionic compounds
or salts
13. Atomic Bonding
Atomic Bond Description
Hydrogen Bonds
Electronegativity
The partial positive charge on
hydrogen atoms that is bonded in
an electronegative atom allows the
hydrogen to be attracted to different
electronegative atoms nearby
Hydrogen bonds maybe
intramolecular or intermolecular
14. Atomic Bonding
Atomic Bond Description
Van der Waals Forces
Weaker than hydrogen bonds
Occur over a very short distance
When many of these interactions
occur simultaneously, they can be
powerful
15. Inorganic Compounds
Also known as Inorganic Biological Molecules
or Micromolecules
These are compounds which are those without
carbon
17. Water
Versatile solvent
Dissolves an enormous variety of solutes
necessary for living
Results from the polarity of its molecules
When water is in liquid form, its hydrogen
bonds are very weak. The hydrogen bonds
form, break and reform with great frequency
18. Characteristics and Functions of
Water
Biological Solvent
Ability to dissolve many substances including
essential molecules in the body
High Specific Heat
Large amount of heat is needed to increase its
temperature, thus it helps in maintaining the
constant body temperature
19. Characteristics and Functions of
Water
High Heat of Vaporization
Conversion of water from liquid to gaseous state which helps an
organism in preventing dehydration
High Heat of Fusion
Helps an organism to maintain constant body temperature at low
temperature
Medium for Chemical and Physical Process
Can serve as a place for gas and nutrient exchange and
elimination of wastes
Means of transport
20. Acids
A substance that increases the hydrogen ion
concentration of a solution
When an acid dissolves in a solution, it donates
hydrogen ions
24. Property Acid Base
pH
Less than 7 Greater than 7
Litmus paper
Blue to red Red to blue
Taste
Sour Bitter
Odor
Burning sensation Often no odor
Texture
Sticky Slippery
Reactivity
Reacts with metal to
produce hydrogen gas
Reacts with several fats
and oils
25. Electrolytes or Salts
Produced when an acid is combined with a base
Conducts electricity within the body
Na+OH- + H+Cl- Na+Cl- + H+OH-
26. Carbon Dioxide
Essential for plants to perform photosynthesis
Waste product from the breakdown of glucose
27. Organic Compounds
Compounds containing carbon bonded to hydrogen
(hydrocarbon)
Carbon atom is the backbone of all macromolecules
30. Macromolecule
Macromolecules are large molecules necessary for life
that are built from different combinations of smaller
organic molecules
Polymers built from monomers such as:
CHO
CHON
CHONP
CHONPS
31. Macromolecule
Polymer
A long molecule consisting of many similar or
identical building blocks linked by covalent bonds.
Monomer
The repeating units that serves as a building
blocks of a polymer