Hi Jenna.
I am waiting for my interview for a MA in Social Work and will wear a long sleeved shirt to cover up my tattoo, but only because I have the same question as you, how are tattoos depicted in the field?
I can tell you now, during lectures at University, it won't matter at all! The culture in the UK re tattoos has changed a lot and they are more and more common nowadays. In my current line of work, in IT, I work with people covered in them and no one bats an eyelid, not even customers or the top executives.
If I go for interviews I just tend to wear a long shirt then it can't be seen. I tend to wear long armed clothes anyway and roll the sleeves up to about a third of the arm so the whole thing isn't showing, just a portion.
I think as long as its tasteful and doesn't have the opportunity to offend someone you should be OK. My tattoo is just a load of birds that span from my wrist to my elbow, so it's no that offensive. Some people may not like it, but it's not like I have offensive material on my arm, birds are seen as peaceful so the tattoo is to represent that a long with freedom.
I still plan to get more in the future, possibly a redesign of the one on my arm, I know the culture in the UK now is less negative over tattoos as they used to be, I work with people covered in them.