What characteristics apply to all species in kingdom protista?

eukaryotic organisms

Explanation:

Protists are eukaryotic organisms that cannot be classified as a plant, animal, or fungus. They are mostly unicellular, but some, like algae, are multicellular. Kelp, or 'seaweed,' is a large multicellular protist that provides food, shelter, and oxygen for numerous underwater ecosystems.

i thinking chemical change

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.