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