You get to unveil the fundamentals of 21st century molecular biology. First, learn the central dogma and the basics of the genetic code, then learn about mutations and the role DNA plays in human development.
After completing this tutorial, you will be able to complete the following:
When does DNA replication occur?
~ DNA replication occurs when body cells are preparing to divide.
What happens during the DNA replication process?
~ DNA helicase unzips the DNA strands. Then, a DNA polymerase enzyme adds free nucleotides inside the nucleus to construct corresponding strands of DNA.
When does DNA mutation occur?
~ Mutuation occurs when a change in the DNA sequence occurs. This can happen because of errors made by the DNA polymerase during replication.
What might cause a mutation?
~ Radiation, X-rays, chemicals, and sudden changes in temperature may cause a mutation.
Is there a difference between the effects of mutations in body cells and the effects of mutations in reproductive cells? Explain.
~ Yes, only mutations that exist in the reproductive cells can affect offspring. Mutations in body cells, however, only affect the person having the mutant DNA; they are not heritable.
Can lung cancer be inherited? Explain.
~ Some forms of cancer are known to be heritable. In these cases, a mutation in a person's reproductive cell DNA is passed to the offspring. The protein created from this DNA code, in the cells of the person's body, is defective and contributes to, or causes, the disease. This is different from cancers caused by mutations to a person's body cells by exposure to chemicals or radiation, which would not be heritable. The majority of cases of lung cancer can be linked to exposure of body cells to harmful chemicals (cigarette smoke, coal dust, and asbestos). These types of lung cancer would not be heritable.
|Approximate Time||2 Minutes|
|Pre-requisite Concepts||Students should be able to define the following terms: cancer, DNA replication, and mutant gene.|
|Type of Tutorial||Animation|
|Key Vocabulary||cancer, DNA replication, mutant gene|