Biology Unit 03
What is a Biomolecule?

Organic molecule
made by living
organisms

Consists mostly of
carbon (C),
hydrogen (H), and
oxygen (O)
But wait…What is an Organic
Molecule?

Organic Molecules:
 Contain carbon
 Considered the “chemicals of life”

Inorganic Molecules:
 Do not contain carbon
Monomers vs. Polymers

Monomers:
 Molecules that may react with similar molecules
to form a chain

Polymers:
 A chain of many monomers that are chemically
bonded together
Animation of Condensation and
Hydrolysis
Click HERE for Condensation and Hydrolysis
Animation
Formation of Polymers

How are polymers formed?
 Dehydration Synthesis (Condensation): Two
hydrogen atoms and one oxygen atom are
removed from the monomers to form water,
and the two monomers are joined together.
Breakdown of Polymers

How are polymers broken down?
 Hydrolysis—the reverse of dehydration synthesis
(condensation)
 Water added to the polymer, un-linking the chain
and breaking it back down to its original
monomer units
Carbohydrates

What are carbohydrates?
 Group of organic molecules that includes sugars,
starches, and cellulose
Carbohydrates

Structure:
 Carbon, hydrogen, and oxygen in a 1:2:1 ratio
 (CH2O)n – n is an integer such as 5 (C5H10O5)
 Subunits: monosaccharides, such as glucose or
fructose
 Most often in a ring shape
 Subunits are connected with covalent bonds.
Monosaccharide Example
Disaccharide Example
Polysaccharide Example
Carbohydrates

Function:
 Energy
 Structural support
 Cell wall
 Cell membrane marker
Lipids

What are they?
 Organic molecule group including fats and
phospholipids
Lipids

Structure:
 Subunits:
○ Glycerol and fatty acids
○ Glycerol and fatty acids plus phosphate group
 Insoluble in water
 Do not form large polymers (2 or 3 fatty acids
with glycerol)
○ Examples: diglyceride and triglyceride
Triglyceride Example
Phospholipid Example
Lipids

Function:
 Energy storage
 Insulation
 Part of cell membrane (phospholipids)
 Hormones
Proteins

What are proteins?
 Group of organic molecules that provides
structure and facilitates chemical reactions.
Proteins

Structure:
 Subunits: Amino acids
 Amino acids connect via peptide bonds
 Very large molecules
 Globular or structural
Amino Acid
Proteins

Function:
 Lots of functions!
 Enzymes (speed rate of chemical reactions)
 Structural components in cells
 Mechanical functions in muscles and
cytoskeleton (internal cell framework)
 Cell signaling
 Immune response
Nucleic Acids

What are nucleic
acids?
 Group of organic
molecules
including DNA
and RNA
Nucleic Acids

Structure:
 Subunits are nucleotides—5-Carbon sugar,
Nitrogen base, and one or more Phosphate
groups.
Nucleic Acids

Function:
 Storage and retrieval of information:
○ Encode genes
○ Gene expression
Information Sources for Diagrams
Capri, A. (2003). Carbohydrates. Retrieved from
http://www.visionlearning.com/library/module_viewer.php?mid=61
Capri, A. (2003). Fats and proteins. Retrieved from
http://www.visionlearning.com/library/module_viewer.php?mid=62
Indiana University. (2013). Fat and why it matters to you. Retrieved from
http://www.indiana.edu/~oso/Fat/SolidNLiquid.html
Cronk, J. (2012). Biochemistry dictionary. Retrieved from
http://guweb2.gonzaga.edu/faculty/cronk/biochem/Hindex.cfm?definition=hydrogen_bond
Chemical Education Digital Library Admin. (2011, January 20). Nucleic acid
structure. Retrieved from Cronk, J. (2012). Biochemistry dictionary.
Retrieved from http://guweb2.gonzaga.edu/faculty/cronk/biochem/Hindex.cfm?definition=hydrogen_bond
Dna structure. (2010, September 28). Retrieved from
http://www.pc.maricopa.edu/Biology/rcotter/BIO
205/LessonBuilders/Chapter 9 LB/Ch9b3.html
Information Sources for this PPT
Shmoop Editorial Team. (November 11, 2008).Biomolecules and the Chemistry
of Life. Retrieved April 6, 2013, from http://www.shmoop.com/biomolecules/
Shmoop Editorial Team. (November 11, 2008).Organic vs. Inorganic Molecules Shmoop Biology. Retrieved April 6, 2013, from
http://www.shmoop.com/biomolecules/organic-inorganic-molecules.html
Shmoop Editorial Team. (November 11, 2008).Monomers, Polymers, and
Dehydration Synthesis - Shmoop Biology. Retrieved April 6, 2013, from
http://www.shmoop.com/biomolecules/monomers-polymers-dehydrationsynthesis.html
Shmoop Editorial Team. (November 11, 2008).Lipids - Shmoop Biology.
Retrieved April 6, 2013, from
http://www.shmoop.com/biomolecules/lipids.html
Shmoop Editorial Team. (November 11, 2008).Carbohydrates - Shmoop Biology.
Retrieved April 6, 2013, from
http://www.shmoop.com/biomolecules/carbohydrates.html
Shmoop Editorial Team. (November 11, 2008).Proteins - Shmoop Biology.
Retrieved April 6, 2013, from
http://www.shmoop.com/biomolecules/proteins.html
Shmoop Editorial Team. (November 11, 2008).Nucleic Acids - Shmoop Biology.
Retrieved April 6, 2013, from http://www.shmoop.com/biomolecules/nucleicacids.html