I understand the structure of simple carbohydrates (di- and monosaccharides, etc.,) but I'm encountering inconsistent/confusing nomenclature while trying to understand the Calvin Cycle. One source shows that "the carbohydrate products of the Calvin cycle are three-carbon sugar phosphate molecules, or 'triose phosphates', namely, glyceraldehyde-3-phosphate (G3P)." Are F6P and E4P also carbohydrates? Are ALL n-carbon sugar phosphate molecules classified as carbohydrates?

  • $\begingroup$ yes they do. you can delete your comment. $\endgroup$ Jul 22, 2021 at 19:28
  • $\begingroup$ Sorry typo. I meant F6P and I meant product. But think about where I’m coming from. The Calvin cycle may have many intermediates, but it is means to convert three molecules of carbon dioxide to a triose phosphate product. The subsequent conversion of triose to hexose may be part of the dark reactions but is not part of the Calvin Cycle. It just feeds into a linear pathway akin to gluconeogenesis. $\endgroup$
    – David
    Jul 22, 2021 at 20:05
  • $\begingroup$ doesn't address my question at all $\endgroup$ Jul 23, 2021 at 12:34
  • 1
    $\begingroup$ If your question is not in the title but about the definition of carbohydrate, you can easily find the answer on the web rather than posting here. Hint: try the Berg chapter on Carbohydrates and the following section 11.1. The phosphate does not contribute to the definition but does not cause an exclusion. $\endgroup$
    – David
    Jul 23, 2021 at 13:53


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