Science Fare

Ever wonder how tiny little seedlings know to send their roots one way and their shoots the other? This behavior is called Gravitropism. While a lot is known about this process, much of it is still a mystery.
Within the tips of growing roots or shoots are specialized cells called statoliths. These cells have one outstanding visible feature. (Visible with a microscope, that is.) Statoliths have tiny grains of starch in their cytoplasm.
A current theory of gravitropism goes like this: The grains of starch, being heavier than the rest of the cell, will settle to the bottom side of the cell. (This action can be observed with a good microscope.) Somehow, and this is the part that is yet unknown, this action results in release or redistribution of the plant hormone auxin on the same side of the statolith. Auxin encourages growth in plant shoots. Thus if a plant shoot is growing sideways the bottom part will receive more auxin and cause the shoot to grow upwards. Plant roots behave the opposite way : Auxin slows growth in plant roots. That has the net result of roots growing downwards.
Although this simple model was proposed in the 1930s, the process still isn’t fully understood. Many organelles, such as the Golgi apparatus and the mitochondria, are thought to be involved in the signal transduction from the starch grain to the production of auxin.

I had just about finished a post about how cool the Unix underpinnings of Mac OS X are. I used as an example the story of how I recovered some deleted files from a compact flash card by simply using the /dev/disk2 “file” and perl. However, that high praise got lost when my computer crashed. So I’ll instead leave you with this story : Blogs are great but remember that browsers don’t save anything when your computer crashes.

Not feeling to inspired to write today. But here are some fun science links:
Danielle thought that these pictures were neat:

(Ultraviolet pictures of the sun from SOHO.)
Caroline likes the Birdhouse cams.