The Fe²⁺ Atom in Hemoglobin Can Be Bonded to 6

question 32

Multiple Choice

The Fe²⁺ atom in hemoglobin can be bonded to 6 coordinate ligands. What are the six coordinate ligands of ferrous iron bonded to?

• A) 4 to the porphyrin ring, 1 to the proximal histidine, 1 to the distal histidine
• B) 4 to the porphyrin ring, 1 to the proximal histidine, 1 to oxygen
• C) 4 to the porphyrin ring, 1 to the distal histidine, 1 to oxygen
• D) 1 to oxygen, 5 to histidines in the hemoglobin polypeptide
• E) the ferrous iron only binds to CO₂

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Definitions:

Maturity Matching

Matching the maturities of debt used to finance assets with the lives of the assets themselves. The debt would be amortized such that the outstanding amount declined as the asset lost value due to depreciation.

Ex Post

An analysis or consideration of events after they have happened, focusing on actual results rather than forecasts.

Asset Lives

The estimated useful life of an asset, determining over what period the asset's cost will be depreciated or amortized.

Compensating Balances

Minimum account balances that a borrower must maintain as part of a lending agreement, often used to offset a portion of the bank's cost in providing the loan.