CO2 a waste product of cell respiration?

[evointrigued]

If glucose is the best starting material for cell respiration, why is Carbon dioxide, the basic component of glucose, a waste product of evolution?

Thanks.

[mith]

Why is CO2 a basic component of glucose?

[evointrigued]

I can't seem to find a place that says that either. This is my word-for-word homework question I'm stumped on:
"If glucose is the best starting material for cell respiration, why, then, is CO2, the basic component of glucose a waste product of cell respiration?"

[evointrigued]

I don't follow what the teacher is looking for.

[mith]

I think the answer your teacher wants has to do with how CO2 is used back in photosynthesis, but I agree that this is a poor question.

[blcr11]

I don't know what the teacher is looking for, either. Maybe it's an ashes-to-ashes-dust-to-dust kind of thing. The CO2 used to make the glucose molecule once upon a time had to come from atmospheric CO2. In order to continue the cycle, glucose has to be broken down into its "basic component", returning CO2 to the atmosphere to be reborn as another molecule of glucose as some future plant fixes it. "It's a vicious soykul..."as Norma Cassady said in her Brooklyn accent, while snapping her chewing gum, in the movie Victor Victoria.

[Ciwan]

I think longandcomp is right about what the teacher wants.

teachers can sometimes be well ...annoying

the other day my teacher asked one of the students..what is glucose? the girl didn't know, so I said it is a sugar, she said yeah but what is it ! then I said it is a monosaccharide sugar that we use in respiration, she said yes, but what is it !! I said I don't know, you tell me what it is, she said it is a molecule isn't it.

I started banging my head against the desk

LOL so annoying