Cell Membranes Are Not Boring
by Michael Keller
To many of us, the image we have of our cells is that which we saw in our biology textbooks. Most are sort of roundish or ovular, though some, like the nerve cells that grow crazy axon tails and dendrite branches, have a more arresting shape.
The textbook and the microscope showed us that there are definitely lots of things going on inside, but the cell itself kind of just sits there and hangs out. The bag that holds all the goo in, the cellular membrane, looks sort of smooth and not really all that interesting.
Except that’s all wrong. Many cells have places to go along with things to do. That’s where structures called filopodia and lamella come in. These projections on the surface of the cell pull it along to where it needs to go, sense chemical signals in the environment and help the cell to interact with other cells.
The gifs above of filopodia waving and retracting on the surface of a cell were made from video created by Physicist Eric Betzig and his team at the Howard Hughes Medical Institute. See the video and read more below.