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How do meroplankton and holoplankton differ over their life cycles?

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Diagram showing ocean zonation by depth and region, with labeled layers: littoral, sublittoral, bathyal, abyssal, and hadal along the seafloor, and epipelagic, mesopelagic, bathypelagic, and abyssalpelagic in open water. The littoral zone is at the high-tide mark. Vertical scale marks photic and aphotic zones from surface to 10,000 meters. — Marine ecosystem Zonation of the ocean. Note that in the littoral zone the water is at the high-tide mark.

In the context of marine ecology, the primary difference between meroplankton and holoplankton lies in the duration of their existence as plankton throughout their life cycles:

Holoplankton are organisms that spend their entire life cycle as plankton, drifting with water currents. Examples include copepods, cladocerans, and krill, which remain planktonic from birth to maturity.12
Meroplankton are organisms that exist as plankton for only a portion of their life cycle, typically during their larval or juvenile stages. Once they reach adulthood, they transition into different habitats, such as becoming bottom-dwelling benthos or nekton. This group includes the larvae of many marine invertebrates, such as starfish, clams, worms, crabs, lobsters, and various fish.12

The larval stage of meroplankton serves several ecological functions, including the dispersal of species for sedentary adults and the exploitation of different environments that may be better suited to the needs of the developing organism than those of the adult.3