1. Unlike glycolysis, in fructolysis the triose glyceraldehyde lacks a phosphate group. 2. The structure of triose phosphate isomerase contributes to its function. 3. Glyceraldehyde is then phosphorylated by triose kinase to glyceraldehyde 3-phosphate. 4. Methylglyoxal synthase provides an alternative catabolic pathway for triose phosphates created in glycolysis. 5. For example, carbohydrates are transported across the inner envelope membrane by a triose phosphate translocator. 6. Photosynthesis produces initially 3-phosphoglyceraldehyde, a three carbon atom containing sugar ( a triose ). 7. Both the ATP and NADPH are used in the Calvin cycle to fix carbon dioxide into triose sugars. 8. A "'triose "'is a monosaccharide, or simple sugar, containing three carbon atoms. 9. This product is also referred to as 3-phosphoglyceraldehyde ( PGAL ) or, more generically, as triose phosphate. 10. Triose phosphate catabolism switches over to MGS when phosphate concentrations are too low for glyceraldehyde-3-phosphate dehydrogenase activity.