Page 175 - PG 101-Course notes مذكرة النظري 24-25 with spec

Medicinal plants (PG 101) Level 1 Clinical Pharmacy-PharmD

Aerobic respiration (4 stages)

Gluconeogenesis is essentially the reverse of glycolysis

Because enzyme catalyzed reactions are essentially reversible, in most cases,

plants can convert pyruvate backwards into sugars for transport and storage. The step

involving phosphofructokinase is virtually irreversible however, so plants have evolved

a different enzyme, fructose-1,6-bisphosphatase to catalyze the conversion of

fructose-1,6-bisphosphate into fructose-6-phosphate in gluconeogenesis.

✓ Gluconeogenesis is important in the metabolism of lipids in plants, but lipid

metabolism is less common in plants than it is in other organisms. Where we

find gluconeogenesis as a critical metabolic pathway is in the germination and

early growth of oil-storing seeds. In these, the stored oils, invested into the seed

by the mother plant, are converted to acetate units, maneuvered back into

pyruvate, backed up into sugars, dimerized into sucrose, and transported to

where growth needs to occur.

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