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