CELL STRUCTURES AND FUNCTION
CELL ORGANELLE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Lipids
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Carbohydrates
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Protein
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Nucleic Acids
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Detailed explanation-1: -Enzymes speed up reactions, often by a factor of a million or more, without themselves being changed-that is, they act as catalysts that permit cells to make or break covalent bonds in a controlled way.
Detailed explanation-2: -The answer is enzymes. Enzymes in our bodies are catalysts that speed up reactions by helping to lower the activation energy needed to start a reaction. Each enzyme molecule has a special place called the active site where another molecule, called the substrate, fits.
Detailed explanation-3: -Two groups of proteins, called cyclins and cyclin-dependent kinases (Cdks), are responsible for the progress of the cell through the various checkpoints.
Detailed explanation-4: -Enzymes accelerate the rates of such reactions by well over a million-fold, so reactions that would take years in the absence of catalysis can occur in fractions of seconds if catalyzed by the appropriate enzyme.
Detailed explanation-5: -1 Answer. Ethan B. Enzymes are proteins which catalyze, or ‘speed up’, chemical reactions.