Questions On the "Human"

I have many questions on the "human". And wonder if scientists 'see" or understand the "human" as more than...

Are "humans" more than the "sum of their parts"? Or are 'humans" just a product of their culmulative "memory"? Are they only geared toward "group think"?

Do "humans' have a "human nature", as a unique individual? Or do "humans" have a "Human Nature", a universal type of 'human nature"? How is this to be understood? How can scientists, who themselves are human, be objective about their own humanity when "observing" the "other human"? Does the very experiment, of objectifying or observing the 'human", create a distance that de-humanizes "the other", the one studied?

Are "humans" different from animals? Is so, how? And, how do we know? Are human only different because of their social structures? Or is the human "mind" something that makes the "human" distinct?

And what is the "human mind"? Can we understand how the brain and mind "connect" when various individuals will respond differently? And how can one have a "control group", when there are so many various memories and personalities that would inhibit creating a "Human Person"?

What is the "common denominator"? Our common denominator is our brain. But, the physical aspects of man are not the determining factor to the "human", only a part.