METABOLISM Flashcards
Two sites on the Hgb molecule
which are prone to oxidation:
- Iron atom (heme)
- Sulfhydryl groups (globin)
RBC relies on________________ for its energy.
anaerobic glycolysis
❖ RBC metabolic processes requiring energy:
Intracellular cationic gradient maintenance
Maintenance of membrane phospholipid distribution
Maintenance of skeletal protein deformability
Maintenance of functional hemoglobin with ferrous iron
Protecting cell proteins from oxidative denaturation
Glycolysis initiation and maintenance
Glutathione synthesis
Nucleotide salvage reactions
principal source of energy
Glucose
Other sources of energy
galactose, fructose, and mannose
RBC membrane is permeable to what energy sources
glucose
RBC membrane is NOT permeable to what energy sources
sucrose, lactose, and maltose
90-95 % of glucose – metabolized by the
Embden-Meyerhof pathway (EMP)
5-10 % of glucose – metabolized by the
Hexose Monophosphate Shunt (HMP)/Pentose Phosphate Shunt
(PPS)
Major source of RBC energy | 90% Anaerobic glycolysis
Requires glucose for energy production
Embden-Meyerhof Pathway
Embden-Meyerhof Pathway Maintains cellular energy by generating
2 ATP molecules
most common deficiency in the E-M pathway
PK (pyruvate kinase) deficiency
Rate of glycolysis ↑ when there is
↑ in the intracellular pH (hypoxia)
Rate of glycolysis ↓ when
ATP levels ↑ and
vice versa
Maintains membrane proteins & lipids, enzymes, hemoglobin iron in its ferrous state
Prevents denaturation of Hb molecule by oxidation
Hexose Monophosphate Shunt/ Oxidative Pathway/
Pentose-Phosphate Pathway