Download FROM TRAIT TO PROTEIN - CLASSROOM

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Part I Proteins are large, complex macromolecules that play critical roles in the body. Proteins are made up of
hundreds or thousands of smaller units called amino acids, which are attached to one another in long chains.
There are 20 different types of amino acids that can be combined to make a protein. The sequence of amino
acids determines each protein’s unique 3-dimensional structure and its specific function.
Proteins do most of the work in the cells and are required for the structure, function, and regulation of the
body’s tissues and organs. In biology this concept has been applied to genes coding for specific proteins such
as insulin, growth hormone, enzymes, and hemoglobin. However, how are the visible traits we see related to
proteins?
In order to understand genetics it is important to understand that GENES CODE FOR PROTEINS. These
proteins are responsible for the visible traits observed in all organisms.
Dimples are considered a mark of beauty and loveliness. However, the truth is dimples are a genetic defect
caused by a fault in the subcutaneous connective tissue that develops in the course of the embryonic
development. The gene mutation causes a shortened version of the muscle protein/fiber to be made. When
a person smiles, the shorter muscle pulls up the facial skin, resulting in a slight depression, which is called a
dimple.
Transfer of dimples (and the shortened connective tissue) is due to just one dominant gene. The dimplecreating-genes if present in both parents will result in a 50-100% chance of their offspring inheriting dimples.
Note: Sometimes a variation of penetrance may occur. Some individuals may carry a particular gene, but they
do not manifest the traits associated with it. Nonetheless, they pass the traits to their offspring.
When the gene code mutation results in dimples the outcome is considered positive – cute dimples!
However, often the gene codes for a protein much more important to the bodies overall function. In class
each group completed a desk model of one of the following genes coding for a specific protein:
*the gene that codes for the protein insulin
*the gene that codes for the protein lactase
*the gene that codes for the protein CTFR
*the gene that codes for the protein hemoglobin
Questions- must answer in complete sentences with question restated and attach to the trait survey
1)
2)
3)
4)
5)
6)
7)
What is a protein and what smaller units (monomers) make up proteins?
What determines each protein’s unique 3-dimensional structure and function?
Provide an example of three proteins coded for by genes (paragraph 2).
What do genes code for?
What causes dimples?
How are dimples inherited?
Where do we obtain most of the amino acids that make up proteins?