Fruitfly Development, Cell by Cell
How can the union of two parental germ cells lead to such complex and varied adult bodies? Sperm meets egg, and a few billion or trillion cells later, you have all the parts of an adult. From humans to fruit flies, we all begin this way.
An intricate (even that word strikes me as painfully inadequate to describe this complexity) chorus of genes turning off and on create cascading waves of signaling molecules. Some molecules say this is top and this is bottom. Others say this is head and this is tail, and still others say that this part will fold and morph and migrate just so, one day becoming your spinal cord or your gut.
We study this developmental dance by watching the embryos of simple animals like fruit flies. What you’re watching above is a new imaging technique that allows every cell in an embryo to be tracked in three dimensions as the organism grows.
By taking images from different sides of the embryo and putting them into powerful computers (11 terabytes of information!), the whole path from egg to larva is drawn. More at the link below.
(via Nature News & Comment)