"Is this a mother?"
I have a question: why was the english translation: is there A mother? Why was the ''A'' added? I know that articles aren't a part of the ukrainian grammar but how could you stress the fact that you are asking ''is there a mother there?'' instead of asking for a specific mother?
You can say "this mother" (ця мати) or "that mother" (та мати) or "my/your/his/her/... mother" (моя/твоя/його/її/... мати) or even "that specific mother" (та конкретна мати) xD
The other camp would be "any mother" (будь-яка мати), "some mother" (якась мати), "any kind of mother" (яка-небудь мати) and so on and so forth
I am not a native ukrainian, but i think it could be just another word for mother...my native language is also a slavic one, and we have also quite a few words for mother like: Мама, Матер, Мати, (the colloquial ones) and Мајка (the standard and most formal one)...kind regards :)