Zooxanthellae
Algae of microscopic size, which live in the tissue of many
types of corals and aid them
by production of oxygen.

Zostro
One of the more widespread types of the sea grasses,
commonly called "eel grass."

Zooxanthellae
Algae often found living within another organism, generally in
a symbiotic relationship.

Zygote
A newly formed diploid cell. the joining of an egg and a
sperm or two spores.

Zooplankton
Those organisms within the plankton that are animals.

Zostera
Eel grass.