The native structure of hemoglobin (hb) comprises of two α and two β subunits, each of which carries a heme group. there appear to be no previous studies that report the in-vitro folding and assembly of hb from highly unfolded α and β globin in a 'one-pot' reaction. one difficulty that has to be overcome for studies of this kind is the tendency of hb to aggregate during refolding. this work demonstrates that denaturation of hb in 40% acetonitrile at ph 10.0 is reversible." (j am soc mass spectrum 2007, 18, 8-16) how many heme groups are present in three hemoglobin protein molecules?

1. seamount a raised footwall block between normal fault creates this 2. syncline break between rocks where a hanging wall rises relative to a footwall 3. hot spring on rolling hills, this a dip between hills 4. volcanic neck created when a block with hanging walls slips down between normal faults 5. caldera underwater volcano that never reaches above sea level 6. horst natural hot water on earth's surface containing many minerals 7. graben underwater volcano whose top is eroded flat by waves 8. crater less than a mile in diameter; looks like a bowl at the top of a volcano 9. guyot magma that filled the central vent that remains after the volcano has eroded 10. reverse fault over 1 mile in diameter; looks like a bowl over a volcano