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VCE Stuff => VCE Science => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE Biology => Topic started by: psyxwar on November 19, 2012, 11:02:16 pm

Title: Does an organelle have to be membrane-bound?
Post by: psyxwar on November 19, 2012, 11:02:16 pm
Hey, I've encountered a little trouble with this question, mainly due to conflicting sources of information. I've been told by a certain biology teacher that organelles are membrane bound, no exceptions, and that "non-membrane bound organelles" do not exist, but other sources seem to suggest otherwise. Can somebody please clear this up for me? Thanks in advanced!
Title: Re: Does an organelle have to be membrane-bound?
Post by: WhoTookMyUsername on November 19, 2012, 11:04:46 pm
My teacher who was extremely good  said they had to be membrane bound, but after considering a whole raft of sources i concluded they did not. It's a definition question and there's not a definitive one. unlikely to come up on exam
Title: Re: Does an organelle have to be membrane-bound?
Post by: Shenz0r on November 19, 2012, 11:05:49 pm
Organelles do have to be membrane-bound. I think you've got an issue with the ribosome, which is not membrane-bound, being classified as an organelle in some textbooks and not in others?

Technically, ribosomes should not be called organelles, but VCAA decides to call them organelles anyway. So, keep in mind that while organelles have to be membrane-bound, ribosomes are an exception. Unless VCAA sends out a memo to teachers saying that ribosomes aren't organelles, you're allowed to refer to them as such.
Title: Re: Does an organelle have to be membrane-bound?
Post by: Scooby on November 19, 2012, 11:06:44 pm
Yeah, VCAA seem to consider the ribosome an organelle, so as far as they're concerned, they don't have to be membrane-bound
Title: Re: Does an organelle have to be membrane-bound?
Post by: psyxwar on November 19, 2012, 11:11:24 pm
My teacher who was extremely good  said they had to be membrane bound, but after considering a whole raft of sources i concluded they did not. It's a definition question and there's not a definitive one. unlikely to come up on exam
Yeah is this Dr S.? He was very adamant and everything haha... Well if VCAA accepts that then I'm fine with that.
 
Organelles do have to be membrane-bound. I think you've got an issue with the ribosome, which is not membrane-bound, being classified as an organelle in some textbooks and not in others?

Technically, ribosomes should not be called organelles, but VCAA decides to call them organelles anyway. So, keep in mind that while organelles have to be membrane-bound, ribosomes are an exception. Unless VCAA sends out a memo to teachers saying that ribosomes aren't organelles, you're allowed to refer to them as such.
So I'd be fine with labelling it as a "non-membrane bound organelle", correct?

Yeah, VCAA seem to consider the ribosome an organelle, so as far as they're concerned, they don't have to be membrane-bound
Yeah if VCAA considers it to be correct then that's fine with me. Thanks!

Thanks for the quick answers guys, very much appreciated!
Title: Re: Does an organelle have to be membrane-bound?
Post by: Scooby on November 19, 2012, 11:19:34 pm
I doubt they'd ever ask you anything like that, since it's a bit contentious. Then again, VCAA decided this year that oxygen is a compound, so you never know...

Anyway, yeah...