what makes me black?

When I fill out applications or other forms that need personal information, where I'm asked for my race/ethnicity, I fill in the bubble that says "Africa American/non Hispanic". Furthermore, my skin is brown and my hair is kinky. So it is understood by myself and others that I am black based on my physical characteristics. But is there more to it? Is my "blackness" based on my culture?
I am from Chicago; not a suburb, the actual city. The area I call home is one of the worst areas in city based on statistics of crime, poverty, murder, and drug usage. I am saying that I am from the "hood". I went to a public school. I enjoy hip hop. I sometimes watch bet. I am fluent in slang/ebonics. I read magazines like King, XXL, and The Source. Are these the things that make me black?
People who are not racially black are sometimes accepted and embraced by blacks if they adhere to black culture. If they dress a certain way, have a certain taste in music, and can speak our language, we may give them and honorary "hood pass". Conversely, a nonblack who follow the culture may be labeled a whigger or poser. How is this distinction made? Where is the line drawn?
Growing up, in my neighborhood I was sometimes made fun of because I used proper english and was often seen reading books like Harry Potter or Holes. Other kids would say I wasn't black. Today I find myself passing the same judgement on some of my peers. Because a black male has chosen to join a white fraternity, wears thong sandals, and only has white friends, I don't identify with him even though his skin is as dark as mine and he fills in the same bubble on applications as I do. What's more is that some white people adhere to the same way of thinking. In the iwu community there some black students that other black students don't see as "black" and when discussing these students' "blackness" with white students, I have witnessed multiple white students say "I am blacker than he/she is". When did black stop being a color and become a status one can achieve? And is that a bad thing? I would love to hear your thoughts.