Use the Following Information to Answer the Question

question 68

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)
Hemoglobin is ________.

• A) a tertiary protein with two polypeptides
• B) a quaternary protein with two polypeptides
• C) a tertiary protein with four polypeptides
• D) a quaternary protein with four polypeptides

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Definitions:

Hyperkalemia

A condition characterized by abnormally high levels of potassium in the bloodstream.

Potassium

A chemical element with symbol K and atomic number 19, vital for nerve function, muscle contraction, and maintaining fluid balance in the body.

Acromegaly

A hormonal disorder that develops when the pituitary gland produces too much growth hormone, leading to enlarged bones in hands, feet, and face.

Enlargement

The process of making something larger or more extensive.