MicrobeHunter.com Microscopy Forum

I suspect they are at the bottom of the food chain. I think I learned that bacteria don't eat and digest but somehow get nutrition by making changes in the chemistry of other life forms. It's a mystery to me. Can anyway explain it?

It depends on the species. Some are autotrophs , which manufacture food internally by utilizing, for instance light through photosynthesis. Others are heterotrophs, absorbing compounds from their environment . Some release enzymes that break certain exogenous compounds down so that they may be absorbed.
Generally, they all must absorb compounds through their cell wall and membrane through diffusion , which must overcome the impermeability of those structures as well as sometimes a concentration gradient, so in some species a form of active transport takes place in order to get needed compounds into the cell.
They cannot engulf anything , like some Eukaryotes can.j

That is really interesting. In some ways the behave more like plants than animals.

DonSchaeffer wrote: ↑

Fri Sep 11, 2020 1:06 am

That is really interesting. In some ways the behave more like plants than animals.

And yet they are neither!

Why are they neither? At one time I think they were considered to be in the vegetable kingdom, along with algae.

DonSchaeffer wrote: ↑

Fri Sep 11, 2020 3:56 pm

Why are they neither? At one time I think they were considered to be in the vegetable kingdom, along with algae.

They are classified under the Monera kingdom. I am no expert but I guess it's because of the differences in how they eat. Like plants some do use Photosynthesis as Phil said and some can use chemosynthesis. Maybe someone with more knowledge can offer a better answer. I do find bacteria to very interesting. I skimmed an article the other day about Cyanogenic bacteria being used to extract precious metals from waste.

https://pdf.sciencedirectassets.com/270 ... ype=client

Kirby

Thanks. They really are interesting--so alien--yet so native to the earth.