"Welcome, welcome, welcome!!! Polly said you might drop by. If you would like, I'll introduce you to some of the real characters that inhabit the wonderful world of cells.
"I'm Chloe the chloroplast. I'm a part of a plant cell. My job is to turn sunlight into sugar! Isn't that a grand job? Plant cells, and animal cells for that matter, are pretty sophisticated. Why don't I let you meet some of the more humble cell folks first.
"These humble cell folks are pretty complex in their own way. They come in many, many shapes.
"They live in every nook and cranny all over the world. Scientists call them bacteria. Sometimes they get a bad rap. Many people only think of bacteria as bad cells. But, the truth is, most do wonderful things for the whole planet, people included.
"Oh! Look who's coming over! It's Simon the soil bacterium! Talk about a good fella!
"You know when people talk about recycling and biodegradable? Well, Simon here does the biodegrading! He takes all that organic material that falls on the ground and breaks it down into small enough pieces for plants to take in through their roots. He does a wonderful job, too. It's hard to see Simon, but without him, you wouldn't be able to see all those plants everywhere.
"Simon has a cell wall all around him for protection; kind of like a suit of armor. Just inside of that, he has a membrane that keeps his insides inside and his outsides outside. And thrown pretty much anywhere inside is his DNA, protein-making factories, energy making devices, his digestive system, and everything else. Simon has pretty much all the same sorts of stuff that plant and animal cells have, only he just throws it wherever it will fit. He's not as organized as plant and animal cells. You probably know people like Simon. You may be like Simon, yourself. So, you know he gets everything done he needs to do, he just doesn't care how he looks when he is doing it!
"Now look who's coming over to see what we're chatting about! It's Ishy the E. coli!
Ishy does the same sort of thing that Simon does, only Ishy lives in animals' intestines instead of the ground. Ishy probably knows some of the E.coli that are living in you right now! Ishy also knows that bad branch of the E.coli family that cause people to get sick. Ishy's not like that! After your stomach has had a chance to grind and gnaw on your latest meal, the food continues down to your intestines. That's where Ishy helps you out. He takes some of the food your body can't digest and he digests it for you. He breaks down some of the big molecules of food into small molecules that are small enough for you to absorb. This works to both Ishy's and your advantage; you feed him and he helps you get more out of a meal!
"Ishy looks a lot like Simon in some ways, doesn't he? Cell wall, membrane and then everything else just tossed anywhere.
"Let's see if there is anyone else around here like Simon and Ishy. We need to keep our eyes pealed for someone who has a cell wall, membrane, and who has everything else mixed together. Let's see. Oh, look over there! There's BeeGee the blue-green algae.
I'm glad I saw him, because I forgot that there are other organisms besides bacteria that don't organize all the stuff inside them. There are also the blue-green alga like BeeGee! Cells like Simon and Ishy and BeeGee are called prokaryotes by the scientists simply because they don't organize their insides. You know Bee Gee does something that Simon and Ishy can't do. Bee Gee, the blue-green algae, can turn sunlight into sugar just like me! Only that stuff is tossed in like everything else he has on the inside. You've probably seen BeeGee or his relatives. They like to live on top of standing water. Remember that bluish stuff you called 'pond scum'? It's okay, you didn't mean anything unkind.
"And there goes Suzie the Spirillum.
"She has those tails, called flagella, to help her swim around. She lives in water and eats dead plants.
"Well, all these bacteria and blue-green algae are pretty important in the world. Some do cause diseases, but many do such helpful things that us plants and animals couldn't live without them!
" Let's go look for plant and animal cells now."
BACTERIAL CELLS: For Parents & Teachers
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