Biomolecules Discussion

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

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.

Animation showing Hydrolysis

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