Enzymes
Enzymes are biological catalysts, made of protein, that speed up chemical reactions in living things.
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Enzymes are biological catalysts, made of protein, that speed up chemical reactions in living things.
- Each enzyme fits one substrate like a lock and key
- High temperatures denature enzymes
- Enzymes work best at an optimum pH
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Enzymes?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Enzymes. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain Enzymes in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Enzymes helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Enzymes in detail
Enzymes are biological catalysts made of protein that speed up reactions in living things without being used up. Each enzyme has an active site with a specific shape that fits only one substrate, described by the lock-and-key model.
Enzyme activity is affected by temperature and pH. Activity rises with temperature up to an optimum, then falls as the enzyme becomes denatured when its shape changes irreversibly. Each enzyme has an optimum pH, such as pepsin in the acid stomach. Enzymes are used in digestion, washing powders and food manufacturing.
How the interactive helps you understand Enzymes
Watch the reaction model in the interactive. Use any sliders or buttons it offers to change the values and see how the reaction model responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Enzymes.
Real-life uses and examples
- Structure a longer answer about Enzymes by moving from definition to example to consequence.
- Explain how Enzymes helps a living thing stay alive, using a plant or animal example.
- Connect Enzymes to health, food and medicine in everyday life.
Common mistakes to avoid
- Listing the steps of a process without saying how one step causes the next.
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Enzymes
What is Enzymes?
Enzymes are biological catalysts, made of protein, that speed up chemical reactions in living things.
What are the most important points about Enzymes?
The main points are: Each enzyme fits one substrate like a lock and key; High temperatures denature enzymes; Enzymes work best at an optimum pH.
Why is Enzymes useful?
Understanding Enzymes helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Enzymes?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Enzymes?
Related topics in Biology include A Balanced Diet, Absorption in the Small Intestine, Leaf Structure.