This document discusses the key biomolecules found in living things: carbohydrates, lipids, proteins, and nucleic acids. It explains that carbohydrates like sugars, starches, and cellulose are used for energy storage and as structural components. Lipids such as fats and oils store energy and make up cell membranes. Proteins have many functions like structure, movement, defense, and catalysis as enzymes. Nucleic acids DNA and RNA carry genetic information and enable inheritance and protein synthesis. The four main biomolecules all contain the elements carbon, hydrogen, oxygen, and nitrogen arranged into larger structures that allow life.

1. he
Chemistry
of LifePrepared by: Jerome A. Bigael,
Leyte Progressive High School

2. The Chemistry of Carbon
The emphasis of this
section is more on
molecules containing
carbon bonded to itself or
other atoms.
We call these C-containing
compounds as organic
compounds

3. Since there are 4 valence
electrons or outermost
electrons in carbon, it is
capable of covalently
bonding with four more
atoms to form straight
chains, branches or even
rings.
All these three forms make-
up the biological
molecules in all living
things.

4. Organic Compound
that contain only
hydrogen and carbon
are called
hydrocarbons.
The covalent bonds
between carbon and
hydrogen are rich in
energy, making them
applicable as fuels.

5. Hydrocarbons
Hydrocarbons are considered nonpolar compounds,
and the equal distribution of electrons maybe
attributed to similar electronegativities of
hydrogen and carbon atoms.
However, most organic molecules inside a cell contain
atoms other than hydrogen and carbon.

6. are molecules that is
present in living
organisms, including
large macromolecules
such as proteins,
carbohydrates, lipids,
and nucleic acids.

7. Generally, these follow the same
laws of nature like other chemical
molecules. However,
biomolecules have specific
functions, especially in a living
system where they commonly act
as a building material.
They are arranged from smaller
and simpler molecules, called
subunits, until they form a more
complex structure called a
macromolecule.

8. Aim: Understand the basis of how
these biomolecules function.
Since water is composed of H and O, it is not
surprising that these elements are among the
most abundant elements in our body.
However, it is also important to note that another
reason for the abundance of C, H, O and N is that
these make up important biological molecules.

9. Element Percentage
H 63 %
O 25.5 %
C 9.5 %
N 1.4 %
Ca 0.31 %
P 0.22 %
CL 0.08 %
K 0.06 %
S 0.05 %
Na 0.03 %
Mg 0.01 %
Distribution of Selected Elements in the Human Body

10. Carbohydrates
 Are chains of small organic molecules with a 1:2:1
mole ratio of carbon, hydrogen and oxygen.
 The simplest formula for carbohydrates is (CH2O)n where
the subscript n refers to the number of carbon atoms.
 Carbohydrates act as energy storage or food reserves
in plants and animals, and this role is attributed to the
many carbon-hydrogen bonds contained in a
carbohydrate molecule.

11. Carbohydrates are important
source of energy needed for
many metabolic activities.
Because of abundance of polar
in its structure, carbohydrates
are highly polar molecules
which can make them soluble
in many body fluids especially in
blood through which they are
carried to all parts of the body.

12. Carbohydrates are generally classified
into 3
Simple carbohydrates or monosaccharides, being
small and therefore may be easily dissolved, provide
instant source of energy.
These are sugars that cannot be
hydrolysed/dissolve to give a simpler sugar.
Examples of monosaccharides include glucose
(dextrose), fructose (levulose) and galactose.
Examples: fructose or sugar found in fruits

13. Disaccharides
A disaccharide (also called a double sugar or
biose) is the sugar formed when two
monosaccharides (simple sugars) are joined by
glycosidic linkage. Like
monosaccharides, disaccharides are soluble in
water. Three common examples are sucrose,
lactose, and maltose.
Example of a disaccharide molecule is milk.

14. Complex or Polysaccharides
Are composed of simple carbohydrates covalently
bonded to each other
Polysaccharides are polymeric carbohydrate
molecules composed of long chains of
monosaccharide units bound together by glycosidic
linkages and on hydrolysis give the constituent
monosaccharides or oligosaccharides.

15. Complex carbohydrates or
polysaccharides, serves as
structural building
for cells.
For example, chitin, it serves
as structural building
material in insects and many
fungi.
Polysaccharide is the main
ingredient on the
exoskeletons of athropods
and crustaecans and also in
cell walls of fungi.

16. Lipids
Lipids are biomolecules that contain large
hydrophobic structures that are commonly not
soluble in water.
The primary function of lipids are storage of energy
and building material for cell membranes.
Cell membranes are selectively permeable, partly
because of the lipid bilayer.

17. Examples of lipids
are :
Fats, Oil and Waxes

18. Polynucleotides
Are chains of nucleotides that play
a role in the storage of information.
Structurally, a nucleotide is
composed of a heterocyclic base, a
pentose (ribose or deoxyribose)
unit, and a phosphate group.

19. The heterocyclic base can have either a
purine (adenine, guanine) or a pyrimidine
(Uracil, cytosine, thymine).
These nucleotides are associated as the
monomeric units of deoxyribonucleic acid
(RNA), which are important carriers of
information inside the cell.

20. The presence of genes, inheritance, and
protein synthesis are possible because of
DNA and RNA molecules.
 DNA is a doubled-stranded long chain
of unbranched polymer, composed of
four types of bases.

21. These bases are adenine= A,
cytosine=C, guanine= G, and
thymine= T.
In DNA, A-T and C-G pairings
are followed.
The DNA carries all genetic
information of an individual.

22. On the other hand, RNA is important in the
transcription and translation of genetic code.
RNA is a single stranded long chain of
unbranched polymer composed of four
types of subunits, namely, adenine= A,
uracil= U, cytosine= C and guanine= G.

23. Base-pairing in RNA occurs during
transcription when RNA strand pairs up with
DNA template strand or when RNA strand
coils up and temporarily pairs up with the
base pairs either in the same or in another
RNA strand
In such cases the A-U and C-G base pairs
are followed.

25. Write the complementary base sequence for the
matching strand in the DNA section shown below.
1. CGTAAGCGCTAATTA
2. TCTTAAATGATCGATC
3. AATGAATAGCTAGCTT
4. GGCATTCGCGATCATG
5. CGTTAGCATGCTTCAT
6. ACTAACGGTAGCTAGC

26. 7. ATGTCGCTGATACTGT
8. GAAGCGATCAGTTACG
9. AATGAATAGCTAGCTT
10. GGCATTCGCGATCATG
11. CGTTAGCATGCTTCAT
12. ACTAACGGTAGCTAGC

27. Proteins

28. Proteins Proteins constitute more
than half of the cell’s dry
weight. The biomolecule
serves many functions, which
includes structural
support(collagen),
movement (muscle),
defense(antibody), catalyst in
a reaction(enzyme), and
transport.

29. Proteins generally contain C, H, N,
and O.
Amino acids are the building blocks
of protein.
They are bi-functional product
containing both a carboxylic group (-
COOH) and a basic group (-NH2)
attached to a carbon atom.