On this page you are required to add two items (link to a website, video, animation, student-created slide show, student-created PowerPoint presentation) and one journal article pertaining to a topic in this chapter.  A one-paragraph summary must accompany each item describing the main idea and how it applies to the lecture topic.  Please see the PBWorks help guide for assistance embedding video and other items directly in the page.  I will also produce a how-to video on using tables to wrap text around items and other useful tips.  Please see the syllabus for organization and grading details.

A) Chapter Summary: This chapter was about mutations in the cells, and how these mutations are most often fixed by forms of DNA repair, and if left untreated, can cause dangerous diseases such as tumors and cancer.

A mutation is a change in the genetic material.  It can be caused spontaneously, from abnormal biological processes, or be induced, from outside environmental agents.  There are different kinds of mutations.  A point-base mutation affects only one base, by either changing the base sequence, or adding or removing nucleotides.  A silent mutation does not alter the amino acid sequence, while a missense mutation changes one amino acid.  A nonsense mutation is when the normal codon is changed to a stop or termination codon, and a frameshift mutation is the addition or deletion of nucleotides that are not multiples of three. 

Mutations that occur in somatic cells are not are not passed on to gametes, however, germ-line mutations are passed on to the offspring.  Cancer is when a mutation occurs in a cell that causes uncontrollable growth.  Cancer can be induced by outside agents, such as carcinogens in cigarettes that can cause lung cancer.  In normal cells, there are things called protoncogenes that can cause cancer if mutated.  These genes promote cell growth, but are carefully controlled and monitored by the cell.  However, if these genes were to become mutated, they would become oncogenes, and probably cause cancer.      

B) Useful Links

1)  Assessing the cytotoxic and mutagenic effects of secondary metabolites produced by several fungal biological agents with the Ames test:  This article from PubMed (submitted 2/04/11), is about how different metabolites produced by fungi were tested with the Ames test in order to see if they were mutagens.  As we learned in class, the Ames test shows whether an agent is a mutagen or not by comparing the the growth of one colony  of His- salmonella with the agent against one with just His- bacteria.

2)  Genes and Mutations: This website (submitted 2/05/11) has useful information about mutations, and goes over topics such as spontaneous and induced mutations, germ-line and somatic cell mutations, and the types of mutations.

3) This picture demonstrates a missense mutation, in which on nucleotide is substituted for something else, causing another amino acid to be put into the peptide and changing the function of the protein entirely.