I believe option B would be the correct choice because, without a catalyst, the reaction will be either too slow or will not happen at all as it would not acquire a fitting activation energy for the reaction.
If you would like to know why the other options are incorrect, please read on:
Option A is incorrect because since proteins are specific in nature, so other protein cannot be replaced, for some other chemical reaction.
Option C is not correct it is a genetic defect that the protein does not form, and all cells are genetically identical, a reaction cannot take place in any parts of the body.
And finally, option D would be wrong because if a forward reaction does not take place, a backwards reaction will not occur.
I hope this answer has helped, and I apologise if somehow this answer finds itself to be incorrect. Good luck on your quiz or homework. :)
The correct answer is: "coevolution" .
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Answer:
The bowl of ice cream contains ice cream with temperature below freezing point. A hot body contains more thermal energy than a cold body. Thermal energy only flows from a hot body to a cold body, and not the reverse.
The bowl of ice cream contain less thermal energy than it sorrounding envoirment (air and the kitchen counter), this creates a temperature gradient that forces thermal energy from the sorrounding envoirment into the bowl of ice cream because, according to thermodynamics, all bodies always tend to be in thermal equilibrium with its sorrounding. The thermal energy flows into the bowl of ice cream until it has the same thermal energy with its sorrounding; bringing the thermal gradient between them to zero.