No, it is a suffix indicating that the person is second singular. There is a verb called '-imek' but you can consider it as zero copula which means the noun is used as a predicate. There is no need for a verb(not a predicate) in a noun sentence. But there is the verb 'olmak' which is the corresponding word for 'to be'.
Kardeşim uzun birisi: My sibling is someone tall.
Yorgun musun?: Are you tired?
Bu elbise güzel: This dress is nice.
Deniz mavidir: The sea is blue.