___culture contains only a single kind of an organism, whereas a mixed culture contains or more kinds of organisms. A _ culture contains a desired organism but also unwanted organisms.

Need ! will give 20 points! what are two ways that diatoms differ from slime molds? the external coverings of diatoms are made up of (silica, chitin or peptidoglycan), while slime molds have cell walls containing (silica, peptidoglycan or chitin). diatoms are (chemoheterotrophs, photoautotrophs or chemoautotrophs) because they make food through photosynthesis, while slime molds are (heterotrophs, phototrophs or autotrophs) because they eat decaying plant matter.