Protists are unicellular eukaryotes so that they contain true nucleus and cytoplasmic organelles like mitochondria, Golgi body, etc.
They show different types of nutrition. Some are photoautotrophs others are heterotrophic. Heterotrophs are saprophytes or parasites. Some protists show animal-like holozoic nutrition.
Some protists possess locomotory organelles like pseudopodia, flagella, cilia, etc.
Protists show both asexual and sexual reproduction.