Biology · Biological Molecules
Work through this past-paper style MCQ, then read the full explanation. Practice more biology questions on mMCQ with adaptive practice and topic analytics.
A 25 years old female with chronic fatigue was diagnosed with iron deficiency anemia and low blood count. What is the cause of her fatigue?
- A
Reduction in amount of Fe-S centers
- B
Lowered production of water from the electron transport chain that cause dehydration
- C
Iron is important for electron transport chain
- D
Iron is important for NADH production
Option C is the correct option because Fe-S clusters mediate electron transfer within and between the respiratory complexes of the electron transport chain so iron is important for the electron transport chain to continue and for ATP synthesis.
Option A is not correct because the reduction in the amount of Fe-S centers doesn't lead to low blood count.
Option B is not correct because lower production of water does not lead to anemia.
Option D is not correct because NADH is a crucial coenzyme in making ATP; it acts as a hydrogen acceptor in an oxidation-reduction reaction and does not require Iron.
This is not correct
Iron is a key component of cytochromes and iron–sulfur (Fe–S) proteins in the ETC.
This is not correct
Iron is a key component of cytochromes and iron–sulfur (Fe–S) proteins in the ETC.
Iron is a key component of cytochromes and iron–sulfur (Fe–S) proteins in the ETC.
In these molecules, iron alternates between Fe²⁺ and Fe³⁺ states to transfer electrons along the chain
This electron flow drives the pumping of protons across the mitochondrial membrane, which powers ATP synthesis.
ETC activity decreases → less ATP production → fatigue worsens (in addition to low oxygen transport from anaemia).
This is not correct
Iron is a key component of cytochromes and iron–sulfur (Fe–S) proteins in the ETC.
Tagged under Biology · Biological Molecules