Two concepts are being conflated into one, which happens when figurative language is used (e.g., "taken away") and used for so long and by so many that it is forgotten that it is figurative. Since rights are not like a pair of shoes that one dons or that one may or may not be permitted to don, they can not literally be taken away as shoes can most decidedly be taken away by heartless (or maybe desperate) individuals. In reference to rights and the United States Founding Documents, "taken away" is a figurative euphemism for oppressed and/or violated. What your professor is wisely asserting is that humankind has innate qualities of dignity and humanity and honor that include the freedom to live under their own volition (though not harm inducing volition, since harm violates a few rights on its own) without the brutality and dehumanization and exploitation of tyrants or greedy mercenaries or other powerful and destructive people or groups. In this sense, these rights are not a negotiable social contract.
In another sense, literal legal rights are a negotiable social contract. Two examples are "We, the people ..." and Swedish health care. In the first example, the groups included in the literal legal social construct of rights as expressed in "We, the people ..." did not include, women, children, slaves, and non-Christian immigrants, and possibly others. This is, in fact a literal legal social construct that forms an agreement between people of a society as to what literal legal rights may be had by whom (though it is speaking of humankind's innate inviolate qualities of dignity, humanity, honor etc, that are not a social construct).
As legal rights, these may--upon a change in the social agreement that results in a change in the social construct--be altered to include or exclude those not previously specified. This is precisely what has happened with Constitutional Amendments, new laws and Supreme Court rulings. On the other hand, no Constitutional Amendments, laws or Supreme court rulings can ever alter the innate humanity and dignity and attendant rights held by every person living--we have already established that these rights may be and are violated and abused, but they can not be altered or disenfranchised.
The second example of Swedish health care is a happy example of inclusion (as opposed to the original exclusion of "We, the people ...") in a literal legal social construct that specifies legal rights that a social group has agreed to. Sweden has agreed that all citizens--because of their innate, inviolate humanity and dignity--have the legal right to any and all needed health care (and education, for that matter) without restriction for any cause.
So, to understand these questions you ask, you must be able to isolated and separate (not conflate) the two concepts of (1) innate human rights and (2) legal rights that devolve to members of a society based upon legal documents that agree to and specify the legal rights recognized within that society. For more clarity, compare the legal social construct of health care rights for citizens in Sweden to the legal social construct of health care rights for citizens in the United States (a political "hot button" right now, I know, but a very clear example of the point I'm making [though I'm not inviting a battle over policy by mentioning it]).