Re: how do germs procreate?

Thanks for the question, Evan. More than one kind of germ exists.

One kind is a bacterium. When there is more than one (and there almost always is more than one around), we call them bacteria. A single bacterium will split into two bacteria when it feels that its environment is correct for it, including how much food is around, whether the temperature is right, among other things. It makes a second copy of its DNA, makes more of the sac that surrounds it (called a membrane), and more of the fluid that sits inside the sac. It becomes larger and pinches off an area down its middle, eventually until it splits into two. It only takes one bacterium to do this, it doesn't need other bacteria in order to reproduce itself. Another kind of germ called a protozoa follows this same pattern.

Another very common kind of germ is a virus. Viruses can't reproduce on their own. They have to use another organism (like a human, or another animal, or even a plant or a bacterium) in order to make more. They invade that organism and use its workings to create many more copies of the virus. These copies escape from the organism that they used (called a host) and wait until they find another one.

Sometimes, a fungus or a complex organism like a hookworm or the parasite that causes malaria can be a germ. They often have options in how to reproduce. Some of them don't require another organism of the same kind to help them to reproduce, and some do. When they need another organism of the same kind, each of these parent organisms provides some DNA (the instructions used to create the new organism) so that the new organism has a mix of DNA from each parent. The new organism then uses that new mixed DNA to make itself, an entirely separate but rather similar version to the two parents.

I hope that answers your question. Please have your parent or a teacher help to explain some of the new words that I wrote above (like organism, parasite, and DNA).

Tim Nicholls, M.D.
Berkeley, CA
Tim