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