Carbon is the main ingredient of organic molecules
- Carbon Skeletons and Functional Groups
- Carbon can form up to 4 bonds with other atoms
- Organic molecules: carbon-based molecules
- Inorganic molecules: non-carbon-based molecules, eg. water/oxygen/ammonia
- Hydrocarbons: organic molecules composed of only carbon and hydrogen atoms
- Two other atoms often in organic molecules are oxygen and nitrogen
- Functional group: A group of atoms within a molecule that interact in predictable ways with other molecules
- Carbon skeleton and functional groups determine properties of org. molecules
- Hydrophilic: attract water molecules
- Monomers and Polymers
- Biomolecules composed of hundreds or millions of atoms
- Monomers: Similar, smaller molecular units
- Polymers: Long chains of monomers linked together
- May be straight chains, branching chains, or chains folding back on themselves
- Thousands of polymers built by fewer than 50 types of monomers
- Four categories of life's main molecules: carbohydrates, lipids, proteins, nucleic acids
- Building and Breaking Polymers
- Dehydration Reaction: When a water molecule is released when a monomer is added
- Polymers must be broken down
- Food is broken down to make monomers available
- Either break down monomers for energy to build new polymers
- Hydrolysis Reaction: When water is added to break bonds between monomers
Concept Check 5.1
1) Draw a molecule that has a three-carbon skeleton and a hydroxyl group on the middle carbon.
2) Explain the connection between monomers and polymers.
Monomers are the small molecular units that are linked together to create polymer.
3) What molecule is released during the construction of a polymer? What is this reaction called?
A water molecule is released during the construction of a polymer in a reaction called a dehydration reaction.
4) Draw at least three ways in which five carbon atoms could be joined to make different carbon skeletons.