Part 2: What’s Shape Got to Do with It? – Cell Form and Function
Cut your morning devotions into your personal grooming. You would not go out to work with a dirty face. Why start the day with the face of your soul unwashed?
-Robert Hooke – discoverer of plant cells
You might be thinking to yourself, after hearing about all of those different types of cells: why would there be so many? Why wouldn’t every type of creature have the same cells? After all you can build a house or a church or a bank out of bricks. But would you want to drive a brick car or wear a brick dress? Do you think a brick water pitcher would even hold water? While you could make a chair out of bricks, perhaps foam cushions would be more comfortable. We use other materials, such as wood, clay, fabric, or glass simply because they work better for the job. In the same way, different types of cells help the creature do different things.
Many bacteria, archaea and some protists look like they have fur or a tail; those are cillia (the hair-like things) or flagella (looks kind of like a tail) to help them swim around. What if the little creature needs to move to find food? Then pseudopods (bits of the cell extending out and retracting) or creeping tendrils work well for searching for and capturing food. What if instead the creature is more plant-like? Since they make their own food, they often do not move at all on their own but instead float along as the ocean takes them.
Plants and fungi both need cells that can give them structure but don’t need to be able to move around, so their cells are both rather stiff. However, I’m sure you’ve noticed that mushrooms are much spongier than say your wooden chair – why? Towering trees need much more rigid cells in order to give them the strength to stand, whereas mushrooms are quite low to the ground and can get by with softer cells. These different types of cells are a gift from the Creator for not only the creatures but for us as well – wood makes much better tables than mushrooms.1
Animals have many different types of cells, each with their own jobs. The rectangular skin cells act like bricks in the wall of a castle, protecting us from the outside world. Red blood cells look like thumb-print cookies – this shape allows them to absorb more oxygen to deliver to our muscles. Those muscle cells are long and thin, and just like the rubber bands they resemble, they stretch and contract as needed to move your arms and legs. Your fat cells, on the other hand, are blobby and round since this shape can store the most stuff. Nerve cells, though, are the coolest; their long tendrils allow them to reach out to one another, to make connections from one cell to the next all throughout your body, so that your brain can tell your feet what to do.
All of these various types of cells illustrates an important concept in science: the relationship between form and function. That is, the way something looks or how it is shaped affects what it does. A paper clip, for example, is made of a rigid material and has a curvy, twisted shape which allows it to hold together papers (or make lovely chain necklaces). What if it were made of jelly? Would it still be able to do its job? What about if it weren’t twisted – could it still hold the papers? In order for the paper clip to do its job, it must have the form that it usually has. Similarly, a red blood cell has been carefully crafted by the Creator into an admittedly unusual shape in order to do its job. Watch for form and function all around you – you will find it throughout all of creation (and the man-made world, too).
1Some people are actually trying to make furniture and other household goods out of fungus mycellium grown inside a frame. Because mycellium can grow very tightly packed together, they actually do make a rather admirable building material...I’m just not sure that I really want that in my house.
