Killer T Cell - The Cancer Assassin
Description: Researchers at the University of Cambridge captured this dramatic footage of killer (cytotoxic) T cells capturing and destroying cancer cells. These white blood cells identify chemicals on the surface of virally-infected or cancerous cells. They then inject chemicals which lead to the death of the infected or cancerous cell. This phenomenon can be used introduce the cell as a basic unit of life or be used in a larger unit on interacting systems or homeostasis.
Web Resources: Body’s ‘serial killers’ captured on film destroying cancer cells - University of Cambridge, Cytotoxic T cells - Wikipedia
White Blood Cell Chases Bacteria
Description: In this dramatic movie from the 1950's a neutrophil chases and engulfs a bacteria. White blood cells like this neutrophil are an important part of our immune system. They will migrate to a site of infection or inflammation through chemotaxis and eliminate invading microbes. This phenomenon will hopefully lead to a number of student questions like: How does the white blood cell follow the bacteria? What happens once the microbe is engulfed? etc.
Web Resources: Neutrophil Chasing Bacteria - About the Movie, Neutrophil - Wikipedia
Hox Genes
Description: Hox genes control the body plan of organisms with each hox gene coding for a specific body part. Hox gene mutations (e.g. a fruit fly with a leg in the place of an antenna) can lead to investigations on development. Similarities in hox genes across various animals can show phylogeny.
Web Resource: Hox genes - Wikipedia
The Potential And Ethics Of CRISPR
Description: CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats. It is an immune system in bacteria that has been co-opted by scientists to create a powerful DNA editing tool. It is a powerful tool that can be used in research and may eventually eliminate certain diseases. However it also could allow humans to create designer babies and through the use of gene drives eliminate certain problem species (like mosquitoes) forever. CRISPR, as a new technology, can be used to give meaning to a unit on inheritance and variation.
Web Resources: CRISPR - Wikipedia, The Ethics of CRISPR - Fast Company
Hemingway’s Polydactyl Cats
Description: The author Ernest Hemingway was given a six-toed cat that his son named Snow White. His former home in Key West, Florida was turned into a museum and houses nearly 50 cats that are ancestors of this original cat. Cats with extra digits are called polydactyl cats and have inherited a dominant gene. Roughly half of the cats are polydactyl. This phenomenon could be used to study inheritance and variation.
Web Resources: Hemingway Cats: The Felines That Rule Papa's Key West Estate - Paw Culture, Polydactyl Cats - Wikipedia
Malaria and Sickle Cell Anemia
Description: Sickle-cell anemia is caused by a single nucleotide mutation in the β-globin gene of red blood cells. This creates incorrectly structured proteins and red blood cells with a characteristic "sickle" shape. This harmful mutation does not affect carriers of the disease. However this mutation can be beneficial in certain areas because it offers protection from malarial infections. This phenomenon can be used in a unit on genetics or evolution.
Web Resources: The Making of the Fittest: Natural Selection in Humans - HHMI, Sickle-cell Disease - Wikipedia
