Futher Examples

Some students have asked for further examples of what we are covering, so I have provided these examples.  They are meant as a supplement to the lecture and the reading, not as a substitute for them.  No questions will be pulled directly from these examples, but they are examples of material that we have covered.

Lesson 1: The 7 Characteristics of Life:  

1A.  Living Things are Composed of Cells: 


1B.  And Living Things are Organized at Different Levels of Organization:

2.  Living Things have Heredity
  • DNA is the molecule of heredity


3.  Living Things Have Metabolism:

  • Living things take in energy (ie light or food) for maintenance and growth. 
  • Living things do this using metabolism, the chemical reactions of life.
  • Metabolism allows living things to respond to their environment:



4.  Living Things have Homeostasis:

  • Living things make changes to keep their internal environment within a certain narrow range. 
  • Shivering is an example of homeostasis to keep the body warm.



  5.  Living Things Grow:

  • Cell division - the orderly formation of new cells.
  • Cell enlargement - cells grow to a certain size and then divide.
  • An organism gets larger as the number of its cells increases.
  • During the filming of the show "Growing Pains," 
    the kids did grow.   :>)


6.  Living Things Reproduce Using DNA:

  • Reproduction is essential for the survival of a species.
  • In the example at the right, the parents reproduce and the child grows.
  • All living things reproduce in one of the following ways:
    • Asexual repoduction - Producing offspring without the use of gametes.
    • Sexual reproduction - Producing offspring by the joining of sex cells.



7.  Living Things Adapt and Evolve in Response To Their Environment:


Lesson 2: The Scientific Method

Scientists think about the world in two ways:

These two ways of thinking about Science lead to Two Approaches to Science

  1. Discovery Science
    In Discovery science, scientists only use observations to learn about the world.  HIV example above.

  2. Hypothesis-based Science
    In Hypothesis-based Science, scientists use experiments to test something about the world.  Observations are used in the experiment.
    An example would be testing the cats with FIV above.

Video on the Scientific Method (is a google video but most players can play it. If it does not work, find the file "NASA_iFile_TheScientificMethod.gvi" found in this folder, right click on it and open it with your video player (VLC, Windows Media Player work).  Or pull it directly from the internet from this link: http://video.google.com/videoplay?docid=8667830033664397807#


Lesson 3: Chemistry

  • Not all substances can be divided down to an atom.    

  • Some things cannot be cut in half, example at right.
  • Molecules are the smallest thing a compound can be 
    and still have the property of that compound.


3 Kinds of Chemical Bonds:
  1. Ionic Bonds 
  2. Covalent Bonds
  3. Hydrogen Bonds (H-Bonds)



Lesson 4: Biomolecules

1. Living things are based on Carbon

2.  There are 4 biomolecules of life (4 families)

  • carbohydrates
  • lipids
  • proteins
  • nucleic acid
  • these molecules are only found in living things or something that was once alive   


3.  Cells build their biomolecules from the four building groups (one for each family of biomolecules)

4. Carbohydrates are the first family of biomolecules

  • simple sugars
  • oligosaccharides
  • polysaccharides
  • cells use them as Energy sources, for building blocks to make other molecules, 
    & as structural materials in cells and in organisms
  • these molecules contain carbon, hydrogen, and oxygen and are polar molecules 
    (dissolve in water)


Carbohydrates that we cannot digest
(such as cellulose) are fiber in our diet.
5.  Lipids are the second family of biomolecules 
(the order or number of the family is not important)
  • they are mostly hydrogen and carbon, making them mostly non-polar molecules
  • they are greasy or oily or waxy molecules and little tendency to dissolve in water
  • They function in energy storage, membrane structure, and coatings
  • fats and phospholipids are made up of glycerol and fatty acids (other lipids are not)
  • triglycerides are the most common fat in your body, have 3 fatty acids combined to glycerol      
  • phospholipids are in membranes, have 2 fatty acids and a phosphate group 
    connected to glycerol
  • phospholipids are unusual lipids because one end is polar (phosphate head) 
    and one end is nonpolar (fatty acid tail)


6.  Proteins

  • Amino acids have:
    • an amino group (NH2 or NH3), 
    • a carboxyl group (COO- or COOH), 
    • and one of 20 varying R groups that varies with the amino acid.
Proteins have 4 levels of structure (abpve right)

7.  The last family of biomolecules are the Nucleic Acids

  • these are polymers of nucleotides
  • nucleotides and nucleic acids are polar (and ionic) molecules 
    made up of carbon, hydrogen, oxygen, and nitrogen
  • They act as chemical messengers of cells, energy carriers (ATP),  
    transport hydrogen atoms and electrons (examples: NAD+ and FAD), 
    as building blocks for nucleic acids.  
  • Nucleic acids serve as the hereditary instructions of all cells (DNA) 
    and in translating DNA to build proteins (RNA)