January 2013 Archives

Today I went into lab to look at some slides under the microscope and take pictures. This is probably my favorite picture. I think starfish in general are interesting, so it was fun to be able to look at one under the microscope. I did some search on interesting facts about starfish and this is what I found.

-If a starfish is chopped into pieces, each piece can grow a whole new starfish (reproduce asexually).
-Starfish do not have eyes, but can sense light and shapes through the tip of their arms called an eyespot.
-The female starfish can produce a million eggs at one time.
-Fertilization takes place outside the body
-If an arm is lost, they can regrow it
-They have two stomachs: cardiac stomach and pyloric stomach
-They can change their gender whenever they want

That would be pretty useful if humans could grow back limbs if they were lost. Maybe someone will do some research on that to see how starfish do that, and if it is possible for humans to get that ability! (research would need to be ethical though!)

Below, I have the websites of the places where I found my information:
http://bestfunfacts.com/starfish.html
http://www.brighthub.com/environment/science-environmental/articles/117491.aspx
http://www.buzzle.com/articles/interesting-facts-about-starfish.html

A biology candidate, Daughters, presented on his previous research today in the science auditorium here at UMM. I thought that this was a good topic because he mentioned in his introduction that in order to understand stem cells, it is important to know a lot about developmental biology. From the early stages of cells, they have to 'decide' what path to take. Humans start out at one cell, and then differential into many, and those cells either because muscle cells or many other types of cells. Daughters mentioned that there are a little more than 200 different types of cells in the human body.

Daughters did his study on mice. He said that where the muscles come from early in development is important on how they react as an adult. All different types of locations of muscles express certain transcription factors that differentiate them from the others. For example, the eye muscle cells express certain transcription factors, while skeletal muscles cells express different transcription factors. Once in their set location, they then all express the same transcription factors, which differentiates them as muscle cells and not skin cells.

Daughters found that heart muscle cells are in a similar location to the jaw muscle cells during early development. He called this the 'cardio-craniofacial field'. Both types of muscle cells express different pathways to get to where they need to be. He found that BMP4 inhibits differentiation into skeletal muscle cells. This enables the skeletal muscle cell to become a heart muscle cell, like a normal one would.

The one thing that I got from this lecture was how amazing it was that he was able to produce heart muscle cells, and that they were able to 'beat'. He has a very good video, showing the heart muscle cells contracting and releasing.