Concept 5.1 Summary

Molecules consist of Carbon=organic molecules e.g: CO2

Molecules do not consist of Carbon=inorganic molecules e.g: H2O, O2

Hydrocarbons ONLY consist of carbon and hydrogen (most of them are fuels such as Methane-CH4).

Different shapes of the carbon backbones:


Straight chain Branched chain



*Each carbon forms four bonds at maximum.

Four common functional groups:
Hydroxyl group(hydrophilic), Carbonyl group, Carboxyl group, Amino group (from up to bottom)


*Together, the carbon skeleton and the attached functional groups determine the properties of an organic molecule.


Polymers are long chains made up of monomers.


Four main categories of life's large molecules:
1. carbohydrates
2. lipids
3. proteins
4. nucleic acids


Dehydration reaction:

• a monomer is added to a chain,
• it removes one water molecule,
• a new bond is formed.

Hydrolysis reaction:

• a water molecule is added to a chain-it breaks a bond beween two monomers.

Concept Check 5.1

1. Draw a molecule that has a three -carbon skeleton and a hydroxyl group on the middle carbone. (Hint: The molecule's formula is C3H8O.)



2. Explain the connection between monomers and polymers.
   Monomers link together into long chains to make a polymer.
   
3. What molecule is released during construction of a polymer? What is this reaction called?
A water molecule is released during construction of a polymer. It is called a dehydration reaction.


4. Draw at least three ways in which five carbon atoms could be joined to make different carbon skeletons.