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. To figure this out, think about what you can’t make out of bricks (or, y’know, anything if you’re playing Minecraft). 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 to make much of what is around us because they simply 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 have cillia (like little hairs) or flagella (one or more “tails”) to help them to move around, like a thousand arms swimming. Other protists have “pseudo-arms” (fake arms that extend and retract as the creature moves) or creeping tendrils that they use to move and find food. There is a protist shaped like a foxglove that uses its “flower” to scoop up food, while its “stem” can coil up like a spring to pull its bell away from danger. Plant-like protists have little need to move since they make their own food (like regular plants), so oftentimes they do not move on their own and just float along as the ocean takes them.
How do plant cells compare to fungi cells? Why are both of them stiff, but plant cells are more rigid? Both creatures require the strength that their cells provide to help them to stand up, but towering trees need much more strength than squat mushrooms. That difference is evident even when touching the squishy mushroom compared to hard tree or even stiff grass (That’s probably why we don’t make tables out of mushrooms. Although, funny story, some 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.).
In animals, our different cells serve different functions. The rectangular skin cells act like bricks in a wall to separate our insides from the outside world. The thumb-print cookie shape of red blood cells allow them to absorb more oxygen or carbon dioxide to carry around the body. The thin muscle cells act like rubber bands, pulling as needed to move our arms and legs. Blobby fat cells are for storing energy, and balls can hold the most volume (amount of stuff inside) of any shape. Meanwhile, our nerve cells connect their “heads” and “tails” together to make a chain that can send electrical signals throughout our bodies, allowing our brains to tell our 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 in spades.