Subject: Why do lotus roots have big holes in them.

I read up from a science magazine and found that lotus root is actually a stem 
and not a root. Then why is it called lotus root then? Why are there big holes 
in the lotus stem? Is there any special reason why the holes are so big? How 
does the lotus plant reproduce. Is it mainly by seeds or is there any other 
ways whereby they can reproduce. Are the seeds light enough to float on water 
or do they sink? All these questions came to my head when I was reading the 
magazine but it does not provide more information on that. I would like very 
much to find out about this plant and I hope you can help. Thank you.Hope to 
hear from you soon.

Re: Why do lotus roots have big holes in them.