major groups of macromolecules are essential for the life of the cell:
carbohydrates, lipids, proteins and nucleic acids. These four
of molecules consist of very large organic compounds with an enormous
in terms of function. Fortunately, the basic concept of their structure
is a simple one: a large number of building blocks (monomers) are
together with covalent bonds to form larger molecules (polymers). Their
unique structures give them a variety of different functions within
systems. Natural selection and the process of evolution is the source
variety in structure and function in these molecules.
to the links
or the outline]
It is often stated
made of organic compounds. What exactly is meant by that statement?
The carbon atoms and
are joined to form different functional groups. How does different
groups affect the different properties (charged, non-charged, bulky,
polar, non-polar etc.) of a molecule?
How do monomers form
via dehydration synthesis?
How are polymers
monomers via hydrolysis?
Note: You need to
recognize different types of monomers and polymers. E.g. assume the
has a figure of fructose. You should be able to recognize it as a type
(simple sugar). A figure of any of the twenty amino acids should be
as an amino acid and so on.
What is a
examples of, and recognize figures of, monosaccharides
What is a
Describe the following three examples of polysaccharides (including
source and function): Starch, glycogen
What is a lipid
How do hydrophobic
compounds differ from each other?
What is the function
oils in living organisms?
Do animals use fats
compare a seal, a marmot and a fox in terms of how they use their
adipose (fat) tissues.
Animals often use fat
as a way to store
energy. Why do animals not typically store energy in the form of
Fats are often
triglycerides. Describe the basic components of a triglyceride.
What is the
unsaturated and saturated fatty acids?
Can you give
one can expect to find unsaturated and saturated fats? Is there a
for why either of these fats/oils dominate in those organisms?
There are other
than triglycerides. Some examples are phospholipids, waxes and
Briefly describe how these differ from each other as well as their
in biological systems.
Give examples of
different kinds of
What is an anabolic
Proteins are very
Give six examples of the different functions proteins can have within
What are the
proteins? How many different kinds of these building blocks are
for human proteins?
Sketch an amino
recognize it on a test?
How are amino acids
to form a peptide?
What is the
the shape of a protein and its function?
denaturation? How does the process of denaturation affect the function
of a protein?
Define the primary
Define the secondary
of a protein (local folding into a helix or a sheet).
Define the tertiary
of a protein. It is crucial that you understand how the shape of a
determines its function.
of a protein (more than one polypeptide unite to form the protein e.g.
hemoglobin). Do all proteins have a quaternary structure?
Who is Linus
he contribute to our knowledge of macromolecules?
What is the role of
in living organisms?
There are two
of nucleic acids in a cell. What are they and how do they differ from
other in structure and function?
What is adenosine
What is the function
the building blocks of nucleic acids?
Describe how the
(nucleotides) are joined together with covalent bonds to form a
Know the general
the double helix and the concept of base pairing (A with T, G with C).
What is the
to the following DNA sequence: ATC CTA AAC GTA?
Lecture Outline Macromolecules: We
will look at four major groups of macromolecules: carbohydrates/
proteins and nucleic acids. These very large molecules fulfill
roles in the cellular realm.
The building blocks of
are referred to as monomers. The macromolecule itself is a polymer.
The process by which the
are joined together to form the polymer is called a condensation
The breakdown of the polymer
to form the monomers is called hydrolysis.
"Carbon water" -
they are formed by the elements C, H and O. If these atoms are counted
in a sugar molecule they will form a multiple of C and H2O. All the
in this group (from the small sugar molecules to the enormous starch
(macromolecule)) are referred to as carbohydrates.
The building blocks of
are referred to as monosaccharides (or simple sugars). Examples of such
sugars are glucose, fructose and galactose.
joined together (e.g. sucrose, lactose or maltose)
together to form polysaccharides.
of simple sugars connected with covalent bonds Examples:
of energy in
animals [liver, muscle] (remember that most of the energy in animals is
stored in the form of fat [triglycerides]); branched structure for
in plants and algae in their cell walls) [all of the three
above are made of glucose units as monomers]
fungi (cell walls) and in exoskeletons of arthropods [e.g. insects and
storage in animals esp in muscle tissue and the liver)
in plants (cell walls))
A group of several types of
molecules. They are all referred to as lipids since they cannot be
in water. They are hydrophobic ("water fearing").
In contrast a hydrophilic
("water loving") compound is attracted to water.
Understand the difference
between hydrophobic versus hydrophilic characteristics in a molecule.
We are studying A. Fats, B.
Phospholipids and C. Steroids in this section.
or Fats/oils (components:
glycerol + three fatty acids)
major types of fatty acids: unsaturated versus saturated fatty acids;
are the building blocks of fats.
of double bonds in an otherwise uniforms chain of carbon and hydrogen
cause kinks in the molecular structure.
fatty acids are prominent in triglycerides with an origin from
fatty acids) [triglycerides] (to the right)
compared to carbohydrates). It is not surprising that animals were
for using fat for energy storage since it is an efficient form of
energy relative to its weight. Plants tend to use starch instead for
energy. Why do you think that is?
in some mammals and birds. Recall the example from class (penguins and
organs have extra
padding of fat)
The diagram to the
a saturated versus an unsaturated fat molecule. Notice the "bulky"
of the unsaturated fat. What do you think are some possible
of this "bulkiness"? In which organisms do you tend to find unsaturated
fats? Why do you think that is?
(glycerol + two fatty acids + phosphate group [polar])
form a bilayer in water. One part of the molecule is hydrophobic while
the other is hydrophilic (this is often referred to as amphipathic).
a basic structural component of the cell membrane. You will learn more
about membranes later. They serve as selective barriers.
steroids (estrogen/ testosterone)
is cholesterol is an important structural componment of cell membranes
in animals (it stabilizes the fluidity of the membrane).
proteins (e.g. keratin
in hair, nails and skin)
amylase that breaks
down starch to maltose)
and human growth hormone)
acids are the building blocks of proteins.
figure above shows the basic structure of an amino acid
(R is the variable
that strongly influences the property of
the amino acids (see
There are 20 different
of amino acids in the human species
not need to
Each amino acid has different chemical properties
(large vs small,
The amino acids
joined by peptide bonds (a type of covalent bond) to form a polypeptide.
The amino acid sequence will
determine the three-dimensional structure of the protein which
is linked to its function. Since life is waterbased their behavior
to water is very important. The protein folds into a unique structure
it is exposed to a water environment.
The structure of
can be viewed as primary, secondary, tertiary and quaternary structure
The three dimensional
of the protein very important for its function.
This shape is
by the solvent (water) as well as surrounding solutes, pH and
Even physical pressure can affect the shape. This is not something that
is critical for us as humans, but for deep sea fish species it is a
Denaturation of proteins
by temperature or chemicals) may inactivate the protein (this may be
by changing its tertiary structure.
carriers and information storage
(a 5-carbon sugar + a phosphate + a nitrogenous base)
4 bases in DNA:
thymine, guanine, cytosine (A T G and C)
4 bases in RNA:
uracil, guanine, cytosine (A U G and C)
to form a polynucleotide (a nucleic acid)
DNA: double helix
two chains of polynucleotides
the structure of DNA in 1953
the bases face
and pair up ( A with T / G with C)
the pairing is
interaction: hydrogen bonds
and Crick the firs clues in regards to how the DNA double
reading these chapters you will have the fundamental knowledge to
biology on a cellular level. Remember to not be intimidated by complex
are learning a lot of new concepts
and structures. It is necessary to use labels to be able to study the
realm and journey further into the field of biology.
Book - Water/ Organic Molecules
overview of water chemistry as well as of the macromolecules with lots
of graphics. The page may take a while to load unless you have a fast
but it is definitely worth the wait.