A. inhibited
B. cooperative
C. catalyzed
D. incomplete
B. cooperative
C. catalyzed
D. incomplete
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Reason through it...it can't be A cuz if hemoglobin inhibited the binding of oxygen binding to it... well we wouldn't be alive.
For the same reason, D wouldn't work. If every hemoglobin incompletely binded oxygen to the protein, then the hemoglobin protein wouldn't be an evolutionarily favoured protein and thus we wouldn't have them. (Note that i'm going to extremes to show you that A and B are ridiculous).
This leaves us with Cooperative and Catalyzed. Catalyzing anything means speeding it up, using less energy than if the normal reaction were to occur. Although this would be really favourable to humans and every creature that uses hemoglobin, it is just not the case.
Hemoglobin has a quaternary structure. This means it is made up of 4 protein subunits. Each one of these 4 heme molecules binds to it oxygen. The rate at which the oxygen binds to the heme molecule is not changing because it has a quaternary structure, it's just allowing for cooperative binding to the quaternary structure.
THEREFORE, the answer is B. Cooperative.
Sorry for rambling on but it's just that i wanted you to understand WHY that was the case. Whenever you get a multiple choice question and you don't know the answer you can immediately elimiate some answers through reasoning like we did with A and D. Something to remember for the future:)
For the same reason, D wouldn't work. If every hemoglobin incompletely binded oxygen to the protein, then the hemoglobin protein wouldn't be an evolutionarily favoured protein and thus we wouldn't have them. (Note that i'm going to extremes to show you that A and B are ridiculous).
This leaves us with Cooperative and Catalyzed. Catalyzing anything means speeding it up, using less energy than if the normal reaction were to occur. Although this would be really favourable to humans and every creature that uses hemoglobin, it is just not the case.
Hemoglobin has a quaternary structure. This means it is made up of 4 protein subunits. Each one of these 4 heme molecules binds to it oxygen. The rate at which the oxygen binds to the heme molecule is not changing because it has a quaternary structure, it's just allowing for cooperative binding to the quaternary structure.
THEREFORE, the answer is B. Cooperative.
Sorry for rambling on but it's just that i wanted you to understand WHY that was the case. Whenever you get a multiple choice question and you don't know the answer you can immediately elimiate some answers through reasoning like we did with A and D. Something to remember for the future:)