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