A producer is like... a green plant or bacterium (plural for bacteria) and it's part of the first level of the food chain. Phototrophs and chemotrophs are two major producers. Phototrophs use the energy from the sun to convert carbon dioxide into carbohydrates, in other words, photosynthesis. Chemotrophs are almost microscopic- they are found in places where water and light are scarce (or rare) or even not there at all.
Sorry if this isn't any help... I'm trying my best, I don't know much. But if it does help, you're welcome! Have a nice day!
This means that certain cells are made by the body for different reasons. For instance, muscular cells are made for muscles, bone for bones, etc.
Hope this helped!
Cells. Because they are the smallest unit of life so they are the basic because they are in every living thing