Zooplankton is what I would put
Epiphyseal plate is the structure within a bone that contains cartilage
cells that divide and increase the size of the bone until adulthood.
The epiphyseal plate, also known as epiphysial plate,or physis, or growth plate, is a hyaline cartilage plate in the metaphysis at each end of a long bone or diaphysis. The plate is found in children and adolescents; in adults, who have stopped growing, the plate is replaced by an epiphyseal line<span>.</span>
It’s main purpose is to protect the cell from its surroundings