Short answers, pulled from the story.
The word organism first entered the English language in the 1660s with a meaning that has since become obsolete, referring simply to an organic structure or organization rather than a living being.
The philosopher Immanuel Kant offered a definition in 1790 that remains influential, describing an organism as both an organized and a self-organizing being.
A siphonophore functions as a single entity while being composed of dozens of specialized zooids that look and act like separate organisms, communicating and coordinating to provide buoyancy, propulsion, and feeding.
Scientists debate whether viruses should be classed as living organisms because they possess their own genes and evolve through mutation and natural selection, yet they lack metabolism and autonomous reproduction.
These early organisms possessed three primary adaptive capacities: replication with moderate fidelity, resistance to decay, and the acquisition and processing of resources.
A lichen consists of fungi and algae or cyanobacteria with a bacterial microbiome, where the fungus provides structure and absorbs water and minerals while the alga photosynthesizes to create a partnership that operates as a single unit.