Biomolcules
Polymer
Polysaccharides
Protein
Lipid/fat
Monomer
Monosaccharide
Amino acid
Fatty acid
DNA
Nucleotide
Role in living things
Store energy
Involved in all cell activities
Stores energy
Makes up cell membrane
Stores genetic information
Biomolecules consist of many elements but there are six main elements. What are they?
What do you think is the most important of these elements? Explain.
I think carbon is the most important of these elements as plants are made up of mostly carbon,
but life would not be possible without the rest of these vital elements.
Biomolecules are mainly held together by what type of bond?
Covalent bonds!
CARBOHYDRATES:
What is the basic definition of a carbohydrate?
A carbohydrate is a biological compound containing carbon, hydrogen, and oxygen that is an
important source of food and energy
What role do carbohydrates play in living things?
Carbohydrates are the body's main source of fuel. Carbohydrates are easily used by the body for
energy. All of the tissues and cells in our body can use glucose for energy. Carbohydrates are
needed for the central nervous system, the kidneys, the brain, the muscles (including the heart) to
function properly.
What is the difference between monosaccharide and polysaccharides?
A polysaccharide is made up of many monosaccharides.
Number of Carbons Category Name
3 Trioses
Relevant Examples
Glyceraldehyde,
Dihydroxyacetone
4 Tetroses
Erythrose
5 Pentoses
Ribose, Ribulose, Xylulose
6 Hexoses
Glucose, Galactose, Mannose,
Fructose
Why do 5 and 6 carbon sugars usually form a ring structure?
Five and six-membered rings are favored over other ring sizes because of their low angle and
eclipsing strain.
Polysaccharide
Origin
Role in living things
Disaccharides
Lactose
Maltose
Sucrose
Any group of two
monosaccharides
Glycogen
polysaccharides
Starch
polysaccharides, complex
carbohydrates
Chitin
polysaccharides
Lactose is a disaccharide or
double sugar as is lactose (also
called milk sugar).
Maltose (also called malt sugar)
is found in beer and malt whisky.
Sucrose - ordinary table sugar
from juices, fruits, and roots - is
a disaccharide or double sugar.
Glycogen is a polysaccharide
found in the liver and muscles
that is easily converted to
glucose for energy
Starch is a natural substance
composed of chains of glucose
units, made by plants and
providing a major energy source
for animals.
Chitin is a tough
semitransparent substance that
forms part of the protective
outer casing cuticle of some
insects and other arthropods,
and the cell walls of some fungi.
What is the role of lipids in living things?

Energy Source

Signaling

Insulation

Nerve Function

Protein Modification
What is a fatty acid and what does it do?
A fatty acid is an organic acid belonging to a group that may occur naturally as waxes, fats, and
essential oils and consisting of a straight chain of carbon atoms linked by single bonds and
ending in a carboxyl group. Formula: CnHn + 1COOH
What is an essential fatty acid?
An essential fatty acid is a natural fat or oil found in whole grains, seeds, nuts, and oily fish,
required in the diet to make prostaglandins.
Describe a triglyceride and its role in living things.
A triglyceride is an ester formed from a molecule of glycerol and three molecules of fatty acids,
considered to have adverse effects on human health when consumed in excessive amounts.
Why does the body make cholesterol? What is it used for?
Cholesterol is the soft, waxy substance is found not only in your bloodstream, but also in every
cell in your body, where it helps to produce cell membranes, hormones, vitamin D and bile acids
that help you to digest fat. Cholesterol also helps in the formation of your memories and is vital
for neurological function.
What is a phospholipid and what are they used for?
A phospholipid is a phosphorus-containing lipid found in double-layered cell membranes. In
addition to functioning as a skin for each cell — keeping the insides in and the outsides out —
phospholipid membranes provide protection from chemicals and pathogens that can derail and/or
destroy the necessary life functions that take place within each cell.
NUCLEIC ACIDS:
Aside from DNA, outline the various ways that living things use nucleic acids.




Encoding information
Transferring information
Reading templates
Fetching amino acids
There are three forms of DNA, A, B, or Z-DNA. Which one is most important to living?
B-DNA and Z-DNA are the only types of DNA found in functional organisms, but B-DNA is
much more common (thus more important).
Concept Description
Facts
Explanation
CHNOPS
Although more than 25 types of
elements can be found in
biomolecules, six elements are
most common. These are called
the CHNOPS elements; the
letters stand for the chemical
abbreviations of carbon,
hydrogen, nitrogen, oxygen,
phosphorus, and sulfur.
A shared electron pair is called a
covalent bond. The number of
covalent bonds that each
element can form is called its
valence.
Carbon chemistry is called
organic chemistry, to distinguish
it from the chemistry of all
other elements.
Most biological molecules are
made from covalent
combinations of six important
elements, whose chemical
symbols are CHNOPS.
Valence and Covalent
Bonding
Organic Molecules
Isomers
Three situations can lead to the
existence of isomers:
1. Structural isomers: Variations
in the position at which
different atoms are joined
together.
2. Enantiomers: Left-handed
and right-handed variations
resulting from the tetrahedral
geometry of carbon.
3. Geometric isomers:
Variations in the placement of
atoms around carbon atoms
joined by double covalent
bonds.
Polarity
Many combinations of different
elements result in unequal
electron sharing, called polar
bonding.
Each element has a
characteristic valence that
determines the number of
covalent bonds it can form.
Hydrocarbons, the simplest
organic molecules, contain only
carbon and hydrogen atoms.
Atoms other than hydrogen can
be joined by single, double, or in
some cases triple covalent
bonds.
Organic molecules exist in threedimensional space, and the same
set of atoms can be put together
in many recognizably different
ways, resulting in molecules
called isomers.
Structural isomers can exist
because of variations in the
sequence by which units are
joined.
Enantiomers can exist because
of the tetrahedral geometry of
carbon.
Geometric isomers exist because
of an alternate arrangement
about a double bond between
two carbon atoms.
Hydrogen bonds are very
common weak bonds that can
attract water molecules to each
other or to other groups. Water
reacts with polar molecules by
forming polar hydrogen bonds,
resulting in solubility.
Functional Groups
The names of the six most
important functional groups
are:
• Hydroxyl
• Carbonyl
• Carboxyl
• Amino
• Sulfhydryl
• Phosphate
Two functional groups
containing oxygen, the hydroxyl
and carbonyl groups, contribute
to water solubility.
Carboxyl groups are weak acids,
dissociating partially to release
hydrogen ions.
Nitrogen in biological molecules
usually occurs in the form of
basic amino groups.
Sulfur is found mainly in proteins
in the form of sulfhydryl groups
or disulfide groups.
In biological molecules,
phosphorus occurs mainly in the
form of acidic phosphate groups.
Biomolecules
Facts
Explanation
Carbohydrates
Functions of carbohydrates
include:
• serving as precursors for
building many polymers
• storing short-term energy
• providing structural building
materials
• serving as molecular "tags" to
allow recognition of specific cells
and molecules
Proteins
Proteins play a wide variety of
functional roles, including:
• enzymes as catalysts, such as
ribonuclease, that accelerate
specific chemical reactions up to
10 billion times faster than they
would spontaneously occur; one
cell may contain some thousand
different types of enzymes at
one time
• structural materials, including
keratin (the protein found in hair
and nails) and collagen (the
protein found in connective
tissue)
• specific binding, such as
antibodies that bind specifically
to foreign substances to identify
them to the body's immune
system
• specific carriers, including
membrane transport proteins
that move substances across cell
membranes, and blood proteins,
such as hemoglobin, that carry
oxygen, iron, and other
substances through the body
• contraction, such as actin and
myosin fibers that interact in
muscle tissue
• signaling, including hormones
such as insulin that regulate
sugar levels in blood
Sugars normally fold up into
ring-shaped rather than linear
forms.
Many common sugars, such as
sucrose, are disaccharides
formed by condensing two
simple sugars.
Polysaccharides, formed by
condensing many sugars, are
abundant energy-storing and
structural biomolecules.
(Cellulose, Starch, Glycogen)
The most abundant and diverse
molecules found in living cells
are proteins.
Amino acids are the building
blocks of proteins.
Amino acids can occur in L- and
D-forms, but only L-forms are
used by cells.
The 20 amino acid side chains
confer different properties,
including solubility in water.
Some side chains are very nonpolar; others are polar, positively
or negatively charged.
The peptide bond that binds
amino acids is one of the
strongest and most durable of
covalent bonds.
As polypeptides are synthesized
by the sequential addition of
amino acids (primary structure),
they begin to fold in several
ways. (Different structures)
Lipids
Important functions of lipids:
• contributing to the structure of
membranes that enclose cells
and cell compartments
• protecting against dessication
(drying out)
• storing concentrated energy
• insulating against cold
• absorbing shocks
• regulating cell activities by
hormone actions
Nucleic Acids
There are two types:
• Deoxyribonucleic acid (DNA),
which serves as a cellular
database by storing an immense
amount of information about all
the polypeptides a cell can
potentially make.
• Ribonucleic acid (RNA), which
occurs in several different forms
(messenger RNA, ribosomal RNA,
transfer RNA) and is needed to
convert DNA information into
polypeptide sequences; in some
viruses, RNA serves as the
primary database with no DNA
involvement; certain RNAs have
catalytic ability similar to that of
protein enzymes called
ribozymes
Nucleic acids are built from
subunits called nucleotides. Each
nucleotide has three
components:
1. a ring-shaped molecule
belonging to the class of purine
or pyrimidine bases
2. a 5-carbon, or pentose, sugar
3. one or more phosphate
groups
Lipids include various
biomolecules whose common
property is their insolubility in
water.
The presence of double bonds
(unsaturation) in fatty acids
changes the melting point of
resulting lipids.
Fatty acids are typically linked to
glycerol, forming glycerides with
one, two, or three attached fatty
acids.
Phospholipids spontaneously
form lipid bilayers, which
generate biological membranes.
Steroids, built from fused ringshaped molecules, include
cholesterol and a number of
hormones.
Nucleic acids, built by
polymerizing nucleotides,
function primarily as
informational molecules for the
storage and retrieval of
information about the primary
sequence of polypeptides.
A small set of purine and
pyrimidine bases are found in
nucleotides and nucleic acids.
Nucleotides can have one, two,
or three phosphate groups.
Nucleotides with two or three
phosphate groups are good
energy donors.
Atoms in each DNA nucleotide
can be identified by specific
numbers. The ends of a DNA
molecule are called 3' and 5'
ends, based on the numbering of
carbon atoms in deoxyribose
sugars
.
Biomolecules Review Quiz:
http://www.phschool.com/science/biology_place/biocoach/bioprop/quiz.html?RADIO1=b&RAD
IO2=e&RADIO3=b&RADIO4=c&RADIO5=e&RADIO6=a&RADIO7=b&RADIO8=b&RADI
O9=e&RADIO10=a&RADIO11=c&RADIO12=e&RADIO13=c&RADIO14=a&RADIO15=e&
RADIO16=b&RADIO17=e&x=118&y=6
1. B
2. E
3. B
4. C
5. E
6. A
7. B
8. B
9. E
10. A
11. C
12. E
13. C
14. A
15. E
16. B
17. E
Functional Groups Review Quiz:
http://www.phschool.com/science/biology_place/biocoach/biokit/quiz.html?RADIO1=d&RA
DIO2=d&RADIO3=b&RADIO4=e&RADIO5=d&RADIO6=b&RADIO7=e&RADIO8=d&
x=117&y=3
1.
2.
3.
4.
5.
6.
7.
8.
D
D
B
E
D
B
E
D