Which model of allosteric protein cooperativity does hemoglobin primarily follow, and how does it incorporate elements of the other model?

• A. Hemoglobin primarily follows the concerted model but incorporates elements of the sequential model.
• B. Hemoglobin primarily follows the sequential model but incorporates elements of the concerted model.
• C. Hemoglobin follows only the sequential model without any elements of the concerted model.
• D. Hemoglobin follows only the concerted model without any elements of the sequential model.

Answer: (A)