Investigating the
three of the four major
biological molecules, including
structure and function within
biological systems.
Biological macromolecules are defined as large
molecules made up of smaller organic molecules.
There are four classes of macromolecules:
,
,
and
.
Together, these elements make up almost all living
things.
•Carbohydrates
are an essential
structural component of living cells
and source of energy for animals;
includes simple sugars with small
molecules as well as
macromolecular substances.
•They
are sugars, starches, and cellulose, which
contain CHO and which function primarily in energy
storage, energy transport, and plant structure.
•A carbohydrate is an organic compound consisting
only of carbon, hydrogen and oxygen. Carbohydrates
can be viewed as hydrates of carbon, hence their
name.
•Lipids
are an essential structural
component in living cells in that they:
ohelp with cell membrane structure
oconstitute a barrier for the cell
ocontrol membrane fluidity
ocontrol the flow of material that go in and out of the cell
oact as an energy storage (fats stored in adipose tissue)
otransmit information in cells
ocan act as a Lipid Vitamin required for metabolism.
•Fats, oils and waxes are all examples of Lipids, which are
molecules necessary for the survival of all living organisms.
•A lipid is composed of a glycerol, a type of alcohol,
attached to three fatty acid chains composed of a carbon
skeleton with attached hydrogen atoms.
•Proteins
play an important role
in the lifespan and quality of
human life.
•Depending on the roles, bonds and the structure of
the amino acid, the proteins in the cell membrane play
the role of:
ochannels to facilitate diffusion and to transfer
molecules according to electrical and chemical qualities
oand as transporters (they bind with glucose molecules
to transport them to the other side of the membrane).
oorganic catalysts in human anatomy
•They also go on to effect the world by being able to
influence the nature of enzymes.
•
•
•
•
Large polymers are made in a process called dehydration synthesis. They
are constructed by linking small monomers (building blocks) together. Each
time two monomers are linked, a molecule of water must be removed.
Dehydration refers to the removal of water and synthesis refers to the
linking of the monomers together.
Small monomers are made in process called hydrolysis. Basically, large
polymers are broken back down into small monomers by the addition of
water.
Hydro stands for the addition of water and lysis means to break.
A monomer is a molecule that is
able to bond in long chains.
Polymer means many monomers
(Poly means many).
Monomers:
Polymers:
Carbohydrates: Monosaccharide
Polysaccharide
Oligosaccharide
Disaccharide
Lipids:
Glycerol
Fatty Acids
Triglycerides
Proteins:
Amino Acids
Polypeptides
Carbohydrates consist of the elements
carbon (C), hydrogen (H) and oxygen
(O) with a ratio of hydrogen twice that of
carbon and oxygen.
In their basic form, carbohydrates are
simple sugars or
. These
simple sugars can combine with each
other(
) to form
more complex carbohydrates (ex:
Glucose). Monosaccharides are
Monomers.
The combination of two simple sugars is
a
(Ex: Sucrose).
Disaccharides are Monomers.
Those with a larger number are called
starch). Polysaccharides are known as a Polymer.
(Ex: Amylose
Basically, a monosaccharide has just one ring, a disaccharide has two, and a
polysaccharide has many.
Fats and oils are made from two kinds of molecules:
glycerol (a type of alcohol with a hydroxyl group on
each of its three carbons) and three fatty acids
joined by
.
A
is a glyceride consisting of one
fatty acid chain covalently bonded to a glycerol
molecule through an ester (the bonding between fatty
acids and glycerol that characterizes true fats) linkage.
A
is a glyceride consisting of two fatty acid
chains covalently bonded to a glycerol molecule through
ester linkages.
Mono- and diglycerides are commonly added to
commercial food products in small quantities. They
act as emulsifiers, helping to mix ingredients such as
oil and water that would not otherwise blend well.
are formed by combining glycerol with three
molecules of fatty acid.
Basically, If only one long-chained carboxylic acid is
bonded, it is called a monoglyceride. If only two
are bonded, it is called a diglyceride. Only with
three is it called a triglyceride.
Proteins are made of Amino Acids, which are composed of carbon,
nitrogen, oxygen, hydrogen and sometimes sulfur.
Amino acids attach to each other by
bonds.
Two amino acids condense to form a
joined together form a
.
to form covalent peptide
, 3 form a
and many
If more than 100 amino acids attach together it is considered a protein.
Primary is the term used to
describe the order of the amino
acids joined together to make the
protein. If the “R” groups in the
Amino Acid structure is replaced
you would have the primary
structure of a particular protein.
Within the long protein chains there
are regions in which the chains are
organised into regular structures
known as alpha-helices (alphahelixes) and beta-pleated sheets.
These are the secondary structures in
proteins.
These secondary structures are held
together by hydrogen bonds.
In an alpha-helix, the protein
chain is coiled like a looselycoiled spring.
In a beta-pleated sheet, the
chains are folded so that they
lie alongside each other.
The tertiary structure of a protein
is a description of the way the
whole chain (including the
secondary structures) folds itself
into its final 3-dimensional shape.
The model shows the alpha-helices in the
secondary structure as coils of "ribbon". The
beta-pleated sheets are shown as flat bits of
ribbon ending in an arrow head. The bits of
the protein chain which are just random coils
and loops are shown as bits of "string".
A protein has quaternary structure if
it is formed of 2 or more subunits
(polypeptides). They are held
together by various forces including
hydrophobic interactions, H-bonds
and ionic bonds.