Enzymes are indispensable for our body's functioning. They come in various forms and play a crucial role in accelerating the chemical reactions within us.

All living organisms rely on thousands of chemical reactions within them for their everyday activities, such as metabolism. The key is maintaining proper balance in these reactions; always having the correct amount of substances is essential.

Raising the temperature can often lead to a faster reaction, which could cause unwanted reactions. Additionally, increasing the temperature to a certain point inside a living creature can damage its cells. Therefore, it is not always a good idea.

Enzymes, produced by living organisms, are known to be powerful catalysts. They need much lower temperatures than most other chemical reactions, helping speed up the beneficial reactions in our bodies. Without them, these processes would take much longer.

A catalyst is a substance that helps speed up a chemical reaction but won't be affected or consumed in the process.

Enzymes are composed of long protein chains, which are, in turn, amino acids. The unique shapes they form by folding the amino acid chains give them the capacity to perform their respective tasks.

Enzymes: catalysts for living organisms

👉 The inner workings of living things feature thousands of chemical reactions simultaneously. Balance and control are essential to ensure the right amount of substances is always present.

👉 Raising the temperature can often help speed up useful reactions but can also lead to unwanted ones. There is, however, a limit to how much you can raise the temperature inside a living creature before its cells become damaged.

👉 Organisms generate enzymes as biocatalysts, which promote faster chemical reactions and make them operate effectively at relatively lower temperatures. In other words, enzymes allow us to accomplish processes more efficiently in our bodies.

👉 Every enzyme is a large protein consisting of chains of amino acids folded into distinct shapes. This particular structure enables the enzymes to carry out their specific functions.

TIP 🤔 🖐️
A CATALYST is essentially a SUBSTANCE that ENHANCES A CHEMICAL REACTION RATE without being altered or consumed. This means it can be used multiple times to increase efficiency and productivity.

Enzymes: unique shapes to catalyse reactions

Enzymes are life's building blocks, enabling various biochemical reactions to occur. They have unique shapes that allow them to bind substrates and catalyse reactions more efficiently. This speeds up the process and yields more desired results due to their higher specificity for certain substrates.

👉 Chemical reactions typically involve breaking down or combining materials.

👉 Every enzyme has a different active site with a shape designed to fit into the substance it needs to interact with, thus enabling the chemical reaction.

👉 Enzymes are very particular and typically can catalyse only one reaction.

👉 To enable the enzyme to function, it has to fit with the substrate in its active site. If the active site doesn't align with that of the enzyme, it won't catalyse a reaction.

👉 The mechanism by which enzymes facilitate chemical reactions goes beyond our simple explanation. The enzyme's active site changes shape as it binds to the substrate, creating an even better fit. This process is called the 'induced fit' model of enzyme action.

Diagram: lock and key model of enzyme action

Lock and key model of enzyme action
The enzyme lock and key model can be illustrated using a simplified diagram.

In the same way, you need the right key to open a lock; an enzyme will only catalyze a reaction if the corresponding molecule fits it perfectly. As illustrated in the diagram above, if there is no match between an enzyme and its substrate, than no reaction will occur.

Enzymes are essential to many biochemical reactions, but their effectiveness relies heavily on their environment. While they can be incredibly effective catalysts when the correct pH and temperature conditions are present, any deviation from those parameters can render them useless. Despite this limitation, enzymes provide a unique solution to many complex biological problems that would otherwise be impossible without them.

Temperature also plays a role

👉 Varying the temperature can alter the pace of an enzyme-driven reaction, making it go faster or slower.

👉 As is the case with any reaction, raising the temperature will boost its rate of occurrence.

The optimum temperature point where the enzyme is most active.

👉 Excessive heat can compromise the integrity of certain enzymes. This alters the shape of the active site, making it incompatible with its substrate and rendering it "denatured".

👉 Every enzyme has an optimal temperature at which it functions most effectively.

So, does the right pH

👉 The pH levels can also influence enzyme activity. If they're either too high or too low, the bonds maintaining the structure of these enzymes can be disrupted.

👉 The form of the active site is altered, and the enzyme is destabilised due to this transformation. It denatures the enzyme.

👉 Every enzyme works best at an optimum pH level, with neutral pH of 7 being the most common. Pepsin is an example of this - it is instrumental in breaking down proteins in the stomach, and its optimal pH is 2, perfect for such a highly acidic environment.

The optimum pH level where the enzyme is most active.
Enzymes act as catalysts; generally, they only initiate a single reaction. 🖐️
Enzymes are vital components of the human body, and understanding their optimal temperature and pH level is critical in maintaining health and well-being. Generally, enzymes work best when operating near average body temperatures. However, enzymes in the stomach work best at a lower pH level than those found in the small intestine. The reasoning is that stomach acidity helps break down food into smaller molecules for digestion. In addition, enzymes found in other body areas may need higher or lower temperatures to be effective.

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