Use the Following Information to Answer the Question

question 9

Multiple Choice

Use the following information to answer the question.
"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?

• A) 3
• B) 4
• C) 9
• D) 12

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Definitions:

Petroleum-Based Fluids

Fluids derived from petroleum used in various applications, including lubricants, solvents, and hydraulic fluids.

Rubber Seals

Flexible components made of rubber, designed to prevent leaks of fluids or gases between different parts.

ISO Flares

Refers to a type of flared tube fitting standard set by the International Organization for Standardization, commonly used in hydraulic and pneumatic systems.

SAE Flares

A type of flare fitting standard set by the Society of Automotive Engineers for secure hydraulic and pneumatic connections.