prokaryotes
algae
zooplankton
the ocean
Thousands of cells
Hundreds of cells
A few dozen cells
Millions of cells
eukaryotes
phytoplankton
Zooplankton are tiny animals.
Just for fun
To see in the dark
To scare away predators
To attract a mate
it makes the water more acidic.
it kills large predators like sharks.
it makes the water saltier.
aquatic (water-living)
plants
drifting or wandering
microscopic
All plankton are microscopic (too small to see without a microscope).