Final answer:
The dinoflagellate belongs to the kingdom Protista because it is a unicellular organism with a flagella and chromosomes held in a nucleus. Protista is the kingdom for eukaryotic organisms that do not fit into other kingdoms.
Step-by-step explanation:
The dinoflagellate belongs to the kingdom Protista. Dinoflagellates are unicellular organisms with a flagella that they use for movement. They have chromosomes held in a nucleus in the cell. Dinoflagellates exhibit great morphological diversity, with many being encased in cellulose armor and having two flagella that fit in grooves between plates, causing a spinning motion.
Protista is a diverse kingdom in the classification of living organisms, including eukaryotic microorganisms like protozoa and algae. These organisms exhibit various modes of nutrition and are typically unicellular or simple multicellular structures. Thus, it is a diverse kingdom that includes eukaryotic organisms that do not fit into the other kingdoms like plants, animals, or fungi.