The Chemicals Of Life

1. BASIC BIOLOGYBASIC BIOLOGY
BIO 101/4 BIO 101/4
Objectives:Objectives:
1.understand that all matters are made up of 1.understand that all matters are made up of
atom/elementsatom/elements
2. list down the main components of life.2. list down the main components of life.
3. how molecules and compounds are formed3. how molecules and compounds are formed
4. the unique properties of water, carbon, lipid, and 4. the unique properties of water, carbon, lipid, and
proteinprotein

2. Atoms & Elements.Atoms & Elements.
*Earth & all lives are made up 92 elements.*Earth & all lives are made up 92 elements.
*Element – the simplest substance, could not *Element – the simplest substance, could not
break into simpler compound by any chemical break into simpler compound by any chemical
means.means.
*4 main elements made up the life:*4 main elements made up the life:
i. Carboni. Carbon
ii. Oxygenii. Oxygen
iii. Hydrogeniii. Hydrogen
iv. Nitrogen iv. Nitrogen

3. *Other elements:*Other elements:
Phosphorus (P), potassium (K), Phosphorus (P), potassium (K),
sulphur (S), sulphur (S), calcium (Ca), iron calcium (Ca), iron (Fe), (Fe),
magnesium (Mg), sodium magnesium (Mg), sodium (Na), and (Na), and
chlorine (Cl).chlorine (Cl).
*Each element made up of atom*Each element made up of atom
*Compound – 2 or more atoms of diff. *Compound – 2 or more atoms of diff.
elements joined together.elements joined together.

4. Molecules and Compounds:Molecules and Compounds:
*covalent bonding*covalent bonding
*ionic bonding*ionic bonding
*valency of element shell*valency of element shell
*organic compound*organic compound

5. CarbonCarbon
* Its special properties:* Its special properties:
i. tetravalent – hold 4 atoms forming i. tetravalent – hold 4 atoms forming
tetrahedron structure, very stable.tetrahedron structure, very stable.
ii. carbon-carbon bond is very strong ii. carbon-carbon bond is very strong
– forming a long chain in a single / – forming a long chain in a single /
combined with other atoms.combined with other atoms.
iii. iii.

6. WaterWater
- essential to life, human body consists - essential to life, human body consists
of 60 - 70% water.of 60 - 70% water.
- consists of 2 Hydrogen atoms & 1 - consists of 2 Hydrogen atoms & 1
Oxygen atom forming 2 covalent bonds Oxygen atom forming 2 covalent bonds
but not equally shared but not equally shared

7. – – Oxygen has a stronger pull on the Oxygen has a stronger pull on the ê ê
than the Hydrogen resulting in than the Hydrogen resulting in
slightly +ve and –ve regions – polar slightly +ve and –ve regions – polar
molecules.molecules.
Water is a dipolar molecule.Water is a dipolar molecule.

9. The unique properties of water:The unique properties of water:
- mainly due to its hydrogen bond - mainly due to its hydrogen bond
that tends to stick to each other.that tends to stick to each other.
i. liquid at RT – 1 water molecule i. liquid at RT – 1 water molecule
could form H-bond with up to 3 could form H-bond with up to 3
other water moleculesother water molecules
ii. Universal solvent – bipolar ii. Universal solvent – bipolar
moleculemolecule

10. iii. surface tension – stronger iii. surface tension – stronger
attraction among water molecules.attraction among water molecules.
iv. Ice float on water – water most iv. Ice float on water – water most
dense at 4dense at 4
oo
C, in liquid the H-bond C, in liquid the H-bond
are constantly formed and reformed are constantly formed and reformed
but in ice the water molecules form but in ice the water molecules form
H-bond w/ 3 other water molecules H-bond w/ 3 other water molecules
and creates a rigid lattice.and creates a rigid lattice.

11. v. adhesion – tendency to wet most v. adhesion – tendency to wet most
surface due to its ability to attract to surface due to its ability to attract to
other molecules – polar property.other molecules – polar property.
vi. High specific heat capacity.vi. High specific heat capacity.
vii. High latent heat of vaporization – vii. High latent heat of vaporization –
creating cooling effect.creating cooling effect.

12. iix. latent heat of fusion – high iix. latent heat of fusion – high
energy lost to form ice crystals.energy lost to form ice crystals.
ix. transparent to sunlight.ix. transparent to sunlight.
x. high densityx. high density
xi. Difficult to compressxi. Difficult to compress
xii. Electric conductor – pure water xii. Electric conductor – pure water
is poor elec. Conductor but dossolve is poor elec. Conductor but dossolve
ions is a good conductor.ions is a good conductor.

13. The significances of water.The significances of water.
i. provides a liquid environment i. provides a liquid environment
inside cells & aquatic organisms.inside cells & aquatic organisms.
ii. Chemical reactions & transport ii. Chemical reactions & transport
mediummedium
iii. Surface tension allows aquatic iii. Surface tension allows aquatic
organisms move on it.organisms move on it.

14. iv. High density of water allow iv. High density of water allow
aquatic organisms to live under ice aquatic organisms to live under ice
during the cool season.during the cool season.
v. adhesion allow water to move v. adhesion allow water to move
upward against gravity in a narrow upward against gravity in a narrow
channel (capillary force) – in plants channel (capillary force) – in plants
(xylem) (xylem)

15. vi. High specific capacity – controlls vi. High specific capacity – controlls
temperature changes – cellular life.temperature changes – cellular life.
vii. High latent heat vaporization – vii. High latent heat vaporization –
cooling effect.cooling effect.
viii. High latent heat fusion – water viii. High latent heat fusion – water
slowly to freeze. slowly to freeze.

17. ix. Transparent – aquatic plants and ix. Transparent – aquatic plants and
microorganisms to photosynthesise.microorganisms to photosynthesise.
x. High density – allow large animals x. High density – allow large animals
to survive in it; whale, ice, etc.to survive in it; whale, ice, etc.
xi. Hardly compressed – acting as xi. Hardly compressed – acting as
hydrostatic skeleton in certain hydrostatic skeleton in certain
organisma like worms & turgid.organisma like worms & turgid.

18. Turgid – composes of Turgid – composes of
85% water & could 85% water & could
dehydrate up to 3% left.dehydrate up to 3% left.

19. xii. Participate in many chemical xii. Participate in many chemical
reaction due to its polar properties.reaction due to its polar properties.
xiii. Low viscosity & high tensile xiii. Low viscosity & high tensile
strength – move freely in small strength – move freely in small
column and reach high up in a big column and reach high up in a big
tree. tree.

20. Water & pH.Water & pH.
* Hydrogen and oxygen atoms of * Hydrogen and oxygen atoms of
water can dissociate to form protons water can dissociate to form protons
and hydroxide ions:and hydroxide ions:
H H
22O O ↔ H↔ H
++
+ OH + OH
--
water water proton hydroxide ionproton hydroxide ion
- pH is measured based on the - pH is measured based on the
concent. of [Hconcent. of [H
++
] in particular ] in particular
solution.solution.

21. Carbohydrates.Carbohydrates.
-Carbon-containing compounds that -Carbon-containing compounds that
supply energy to our body.supply energy to our body.
-contains carbon, hydrogen, & oxygen – -contains carbon, hydrogen, & oxygen –
CC
xx(H(H
22O)O)
yy, x & y are variables that could , x & y are variables that could
be the same/diff.be the same/diff.
-eg: table sugar, starch, cellulose, & -eg: table sugar, starch, cellulose, &
glycogenglycogen

22. -types of carbohydrates:-types of carbohydrates:
1. monosaccharides1. monosaccharides
2. disaccharides2. disaccharides
3. polysaccharides3. polysaccharides

23. MonosaccharideMonosaccharide
-the simple type of sugar – (CH-the simple type of sugar – (CH
22O)O)
n, n,
n = 3 – 7, n = 3 – 7,
triose, tetrose, pentose,hexose,heptosetriose, tetrose, pentose,hexose,heptose
- glucose is the best known and most - glucose is the best known and most
abundant sugar – Cabundant sugar – C
66HH
1212OO
6.6.
glucose, fructose, galactose.glucose, fructose, galactose.
-glucose has two common isomers: -glucose has two common isomers:
alpha & beta based on the position of alpha & beta based on the position of
its hydroxyl group on Cits hydroxyl group on C
11

25. Disaccharides.Disaccharides.
- two monosaccharides forms - two monosaccharides forms
disaccharide thru disaccharide thru condensation condensation
process / water removalprocess / water removal
- alpha glucoses - alpha glucoses → starch} glycosidic → starch} glycosidic
beta glucose → cellulose} bond beta glucose → cellulose} bond

28. eg: maltose eg: maltose → 2 glucose molecules → 2 glucose molecules
sucrose → glucose & fructosesucrose → glucose & fructose
lactose → glucose & galactoselactose → glucose & galactose
-Di/polysaccharides could be broken -Di/polysaccharides could be broken
into its constituents thru into its constituents thru hydrolysishydrolysis..
-3 to 10 monosaccharides form -3 to 10 monosaccharides form
oligosaccharide.oligosaccharide.

29. PolysaccharidesPolysaccharides
-long chain of monosaccharides -long chain of monosaccharides
linked by glycosidic bond & linked by glycosidic bond &
normally insoluble in water, not normally insoluble in water, not
sweet.sweet.
eg. Starch, cellulose, glycogeneg. Starch, cellulose, glycogen
-the monosaccharides could be joint -the monosaccharides could be joint
in many ways; straight, branched, or in many ways; straight, branched, or
coiled. coiled.

30. -the properties of polysaccharides -the properties of polysaccharides
are determined by the # and types of are determined by the # and types of
monomers and how it jointed.monomers and how it jointed.
- the monomers are joint thru their - the monomers are joint thru their
hydroxyl groups.hydroxyl groups.

32. starchstarch- energy storage in plants, formed - energy storage in plants, formed
by alpha glucose units, broken down for by alpha glucose units, broken down for
respirationrespiration
- 2 common types; amylose & - 2 common types; amylose &
amylopectin.amylopectin.
AmyloseAmylose – linked by 1-4 glycosidic bond. – linked by 1-4 glycosidic bond.
AmylopectinAmylopectin – linked by both 1-6 & 1-4 – linked by both 1-6 & 1-4
glycosidic bonds.glycosidic bonds.

35. -chloroplast is a type of plastics made -chloroplast is a type of plastics made
up of starch.up of starch.
GlycogenGlycogen – energy storage in animals. – energy storage in animals.
- has more branches than starch (1-6 - has more branches than starch (1-6
glycosidic bond), less dense and more glycosidic bond), less dense and more
soluble, found commonly in liver and soluble, found commonly in liver and
muscle cells.muscle cells.

36. -hydrolysed more rapidly than starch -hydrolysed more rapidly than starch
due to its bonding type.due to its bonding type.
CelluloseCellulose – major constituent in plants – major constituent in plants
and tougher structure.and tougher structure.
- formed by beta monomer unit, not - formed by beta monomer unit, not
readily hydrolyzed by common enzymes.readily hydrolyzed by common enzymes.
- herbivores have microorganisms - herbivores have microorganisms
producing cellulase to digest cellulose.producing cellulase to digest cellulose.

37. -cellulose is permeable to water and -cellulose is permeable to water and
other substances to enter/leave plant other substances to enter/leave plant
cells freely.cells freely.
Lignin – complex cellulose Lignin – complex cellulose
impregnated with non-carbohydrate impregnated with non-carbohydrate
materials lining cell wall/tube like materials lining cell wall/tube like
xylem.xylem.

40. LipidLipid
- insoluble compound in water bur - insoluble compound in water bur
dissolve readily in other organic dissolve readily in other organic
compounds like ethanol, diethyl compounds like ethanol, diethyl
ether.ether.
-common type of lipid is triglycerides -common type of lipid is triglycerides
made up of fatty acids and glycerols made up of fatty acids and glycerols
thru condensation process; linked by thru condensation process; linked by
ester bondester bond

42. -glycerol is a type of alcohol.-glycerol is a type of alcohol.
Fatty acids – a long hydrocarbon chain Fatty acids – a long hydrocarbon chain
w/ acidic carboxyl group.w/ acidic carboxyl group.
- 1 molecule glycerol could combine w/ 3 - 1 molecule glycerol could combine w/ 3
mol. of fatty acids; could be the same mol. of fatty acids; could be the same
type or diff. type.type or diff. type.
-triglycerides: oils (liquid)-triglycerides: oils (liquid)
fats (solids) fats (solids)

43. -2 types of fatty acids:-2 types of fatty acids:
i. saturatedi. saturated
ii.unsaturatedii.unsaturated
the atoms around double-bond C the atoms around double-bond C
atom could be arranged in atom could be arranged in ciscis- or - or
transtrans-form.-form.

44. -high # of cis-double bond tend to be -high # of cis-double bond tend to be
liquid and trans-form tends to be solid. liquid and trans-form tends to be solid.
Significance of lipids:Significance of lipids:
i. provides more energy due to its i. provides more energy due to its
higher H-contenthigher H-content
ii. Heat insulationii. Heat insulation
iii. Shock absorptioniii. Shock absorption
iv. Buoyancy – aid single-celled iv. Buoyancy – aid single-celled
aquatic animals to be on the surface.aquatic animals to be on the surface.

45. -phospholipids is a major component -phospholipids is a major component
of cell membrane and also myelin of cell membrane and also myelin
sheath.sheath.
- consists of glycerol attached to 2 - consists of glycerol attached to 2
fatty acids w/ the 3fatty acids w/ the 3
rdrd
hydroxyl group hydroxyl group
attach to phosphoric acid make it attach to phosphoric acid make it
polar portion.polar portion.
**amphipathic propertyamphipathic property..

48. Protein.Protein.
-large & complex molecules, make up -large & complex molecules, make up
18% of human body.18% of human body.
- thousands types with a unique 3-- thousands types with a unique 3-
dimensional structure that enables it dimensional structure that enables it
to play diverse function in organism to play diverse function in organism
life.life.

49. 7 groups of proteins based on their 7 groups of proteins based on their
functions:functions:
11. enzymes- catalyzes biochemical . enzymes- catalyzes biochemical
reaction; breakdown & formation of reaction; breakdown & formation of
ATP.ATP.
22. structural proteins- forms parts of . structural proteins- forms parts of
animal body; ligament & tendon animal body; ligament & tendon
(collagen)(collagen)

50. 33. signal proteins – carry messages . signal proteins – carry messages
around the body; insulin, hormonearound the body; insulin, hormone
44. contractile proteins – involve in . contractile proteins – involve in
movements of our body; myosin & movements of our body; myosin &
actin for muscle contractionactin for muscle contraction
55. storage proteins – eg. Albumin in . storage proteins – eg. Albumin in
white yolkwhite yolk

51. 66. defensive proteins – antibodies.. defensive proteins – antibodies.
77. transport proteins - heamoglobin. transport proteins - heamoglobin

52. Amino acids.Amino acids.
- building block of protein- building block of protein
- all a.a have amino and carboxyl - all a.a have amino and carboxyl
groups in their general structure.groups in their general structure.

55. -The amino and hydroxyl groups, Hydrogen -The amino and hydroxyl groups, Hydrogen
atom & side chain (R group) are attached by atom & side chain (R group) are attached by
covalent bond to a central carbon atom covalent bond to a central carbon atom
called called αα-carbon-carbon..
R-groupR-group could be a single H-atom or a could be a single H-atom or a
complex ring structure, it could be polar or complex ring structure, it could be polar or
non-polar.non-polar.
Polar proteins readily dissolve in Polar proteins readily dissolve in
water/cellular solution – transported easily. water/cellular solution – transported easily.

56. Amino acids are Amino acids are amphotericamphoteric; having ; having
both acidic and basic properties, both acidic and basic properties,
make it a good buffer.make it a good buffer.
2/more amino acids can be joint 2/more amino acids can be joint
together by a peptide bond to form together by a peptide bond to form
dipeptide/polypeptide.dipeptide/polypeptide.

59. Protein structure.Protein structure.
4 levels of protein structure:4 levels of protein structure:
i. primaryi. primary
ii.secondaryii.secondary
iii.tertiaryiii.tertiary
iv.quaternary.iv.quaternary.

60. Primary structurePrimary structure – a single chain of – a single chain of
polypeptide. polypeptide.
SecondarySecondary – folding/coiling structure – folding/coiling structure
due to forces between diff. part of the due to forces between diff. part of the
molecules forming alpha-helix/beta-molecules forming alpha-helix/beta-
pleated sheet structure.pleated sheet structure.

63. Tertiary structureTertiary structure – 3D shape of – 3D shape of
polypeptide chain & could be polypeptide chain & could be
classified into 2 groups:classified into 2 groups:
i. fibrous protein – insoluble in i. fibrous protein – insoluble in
water & physically tough. It is along water & physically tough. It is along
polypeptide chain linked together.polypeptide chain linked together.
Ii. Globular protein – tightly Ii. Globular protein – tightly
folded polypeptide forming spherical folded polypeptide forming spherical
shape.shape.

64. Quaternary structureQuaternary structure – consists of – consists of
more than one polypeptide chain more than one polypeptide chain
bonded together. eg. Haemoglobin bonded together. eg. Haemoglobin
structure – 4 polypeptide chain w/ 2 structure – 4 polypeptide chain w/ 2
diff. types; alpha and beta chains.diff. types; alpha and beta chains.