The Quaternary Structure of Hemoglobin Changes from the T State

question 50

Multiple Choice

The quaternary structure of hemoglobin changes from the T state to the R state .

• A) only after four molecules of O₂ are bound
• B) after the binding of one molecule of O₂ causes a change in the primary structure
• C) when hemoglobin is completely deoxygenated
• D) when at least one subunit on each dimeric unit αβ dimer) is oxygenated

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Definitions:

Lac Operon

An example of gene regulation in prokaryotes, involving a group of genes that are involved in the transport and breakdown of lactose in the cell.

Repressor

A substance, often a protein, that inhibits the expression of a gene.

Differentiated Cell

A cell that has developed and specialized to perform a specific function in the body.