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