Summary of 5.1

Concept 5.1: Carbon is the main ingredient of organic molecules.

Key Terms:
organic molecule -- carbon-based molecule

inorganic molecule -- non-carbon-based molecules
hydrocarbon -- organic molecule composed of only carbon and hydrogen atoms
functional group -- a group of atoms within a molecule that interacts in predictable ways with other molecules.

hydrophilic -- attracts water molecules

monomer -- small molecular unit that is the building black of a larger molecule

polymer -- cells link monomers together into long chairs.

Notes:

Carbon Skeletons and Functional Groups
* carbon atoms are so common in living things
-carbon has 4 electrons

-can hold 4 bonds with other atoms
-other atoms can branch off into four directions
* carbon can form bonds with one or more other carbon atoms endlessly

-carbon-based molecules (organic molecules)
-non-carbon-based molecules (inorganic molecules)

-ex. water (H2O), oxygen (O2), and ammonia(NH3)

* can bond with carbon atoms, and other elements

-ex. composed of only carbon and hydrogen (hydrocarbons)
* most organic molecules that contain hydroxyl groups are hydrophilic

-"water-loving"

Monomers and Polymers
* biomolecules maybe composed of hundreds or even millions of atoms

-molecular units: monomers

-many monomers together; form into long chain: polymers

* every living cells has thousands of different kinds of polymers

-vary from cell to cell within an organism

-all of these polymers are formed by fewer than 50 kinds of monomers

* life's large molecules are classifies into four main categories: carbohydrates, lipids, proteins, and nucleic acids.

Building and Breaking Polymers

* when monomer is added to a chain, a water molecule is released (dehydration reaction)

-de:removing hydro: water

* organisms build and break polymers down

-ex.many of the molecules in your food are polymers

-we need to break down large molecules into small pieces

* cells break bonds between monomers by adding water to them, the reverse of dehydration (hydrolysis reaction)

-hydro-: water -lysis: break down

Concept Check 5.1

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

2. Explain the connection between monomers and polymers.
Connection between monomoers and polymers are monomers are molecules that are large molecules built from many similar, smaller molecular units; and polymers are a long chain which is made out of many monomers.

3. What molecule is released during construction of a polymer? What is this reaction called?

Water is released during constrution of a polymer, and this reaction is called dehydration reaction.

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