Final answer:
The concept not key to human culture as discussed in the lecture is 'Culture is isolated', because culture is fundamentally about shared symbols, meanings, and norms that evolve and spread across generations.
Step-by-step explanation:
The concept that is NOT key to human culture as discussed in the lecture is 'Culture is isolated'. Culture is a dynamic system consisting of shared symbols, meanings, norms, and a wealth of social constructs contributing to various forms of cultural expression and societal behavior. It encompasses everything from knowledge, belief, art, morals, law, to custom, and is characterized by its ability to be shared, learned, and transformative across generations through processes such as innovation, discovery, and cultural diffusion. The notion of culture as being isolated contradicts the fundamental understanding of culture as inherently shared and continuously influencing and being influenced by other cultures.