Many students cannot distinguish the difference between
a genetic disorder and a disease. Cavities, earaches, and skin boils
are caused by bacteria. The common cold, AIDS, measles, and cancer
are all caused by viruses. Sickle cell anemia and hemophilia are
genetic disorders. If students are not clear or unaware of what heredity
and genetics are, you may want to discuss that certain characteristics
of humans are genetic, or carried on from one family generation to another
How do you determine which characteristics are genetic?
Ask the students to look at their neighbor's ear lobe and observe if the
ear is attached to his face or if it is free. This is a genetic trait
within families. If you can roll your tongue, if your thumb bends
back, your eye color, and your hairline type are all genetic traits that
are inherited. The direction of your hair growth, or hair whorl is
also genetic. These are characteristics that do not adversely affect
the human body, but some genetic traits can cause severe damage to a human
body. The chances of getting a genetically impairing trait are statistically
linked to recessive and dominant gene pools.
- To illustrate this to your students, get a
piece of 8 1/2" x 11 paper and randomly place one or two colored lines
on the paper (short direction). This represents a "genetically transmitted"
trait that will result in a disorder. Cut out 4 paper dolls, by folding
the paper in half. (This represents how many children were born by
parents with the trait.) Some genetic mishaps are not inherited, but represent
a departure from the average human genetic make up. In other words,
not all the children will have the disorder.
- Ask the students if they can determine whether an
illness is bacterial, viral, or genetic. You may want to make a list as
they bring each disease up.
| sickle cell anemia
- You can use the recommended book, Germs Make me
Sick and see if students can critique the book for correctness. For
instance, is the term “germ" appropriate. “Germ” is not
a scientific name, but yet the book makes it appear that it is.
There are also other mistakes like there should be a picture of a virus
when it really is a bacterium. Students should critique whether
the students who read the book would really understand the difference of