Final answer:
Enzymes are biological catalysts that lower the activation energy needed for reactions to occur. Without enzymes, higher temperatures and larger proteins would be required to sustain life.
Step-by-step explanation:
Enzymes are biological catalysts that speed up chemical reactions in living organisms. Without the presence of enzymes, the reactions necessary to sustain life would require higher temperatures and larger proteins. Enzymes lower the activation energy needed for a reaction to occur, allowing it to happen at lower temperatures and with smaller, more manageable proteins. Therefore, without enzymes, larger cells, higher temperatures, and larger proteins would be required to sustain life.
Learn more about The role of enzymes in sustaining life