Translation:Klingons call Kronos "the homeworld".
If you mean the apostrophes ', then yes -- they are a Klingon letter just like a or b. Leaving them out would be like leaving out any other letter.
For example, Qo'noS is the Klingons' home planet but QonoS is a journal or log -- a completely different word.
Or do you mean the quotation marks around "the homeworld" in the English translation?
In that case, they're currently required, yes -- Duolingo generally ignores punctuation such as commas or periods but seems to be strict about quotation marks.
I suppose a case could be made for adding the version without quotation marks as an accepted alternative.
Re: "I suppose a case could be made for adding the version without quotation marks as an accepted alternative." Please do as all other punctuation is optional (for which I am very thankful). I was scratching my head for a while trying figure out why my word order was wrong (it wasn't) and then trying to find what I had misspelled (nothing)!
You'd think. The noise is the sound of my finger on the touchpad, from starting the recording. I'm not sure why sometimes it's louder. There's no opportunity on Duolingo to edit sound files, so I have to re-record the whole sentence, which I can't do right now because someone else here is watching television.
I have re-recorded this one, but it won't update for a few days.