Olfactory receptors are specific to one type of odorant molecule. The combination of receptors which are activated tell your brain what you are smelling. For example, if one certain smell receptor binds hexanoic acid (a 6 carbon chain with a carboxylic acid attached) only one receptor recognizes it and you will smell sour and goat-like. But if your receptors bind nonanoic acid (a 9-carbon chain with a carboxylic acid attached) about eight different receptors will recognize it, and you will smell cheese and nuts.
Genes that code for different colors (GFP = green fluorescent protein, RFP = red, YFP = yellow, CFP = cyan) get put into the DNA of the mice. They also add a gene for a molecule called “Cre recombinase” that randomly cuts out one or more color. So each cell has its own combination of colors that shows up in a microscope. This allows scientists to track one individual neuron to see where it starts and ends. It also makes some pretty awesome images!
Unicorns have been a bigger deal in history than I gave them credit for. Alexander the great claimed that he once rode a unicorn into battle.
If you’d like a unicorn of your own, the Lake Superior State University in Sault Ste. Marie, Michigan has been giving out permits for going after unicorns since 1971. Perhaps if you get dehydrated enough, you’ll find one.
For more on bioluminescence, feel free to check out the old comics about it!
News on the Ferret front! There is now an official Forbidden Ferret android application. It’s a simple comic viewer that allows you to browse all the ferret comics with simple swipes of your finger! With any luck, there will be an iOS application soon to follow as well. If that strikes your fancy, check it out!