PRAKTIKUM ENZIM KATALASE (Materi Metabolisme), Biologi Kelas XII Semester Ganjil

Summary

In this video, Mrs. Dwi Usir demonstrates a practicum on the catalase enzyme, exploring its role in breaking down hydrogen peroxide into water and oxygen. The video examines how factors like temperature and pH influence the enzyme's effectiveness. Different experiments show that the catalase enzyme works optimally at a neutral pH of 7 and room temperature (around 30°C), while cold and hot temperatures, as well as acidic or alkaline environments, reduce its efficiency. This experiment highlights the importance of optimal conditions for enzymes to function properly.

Takeaways

• 😀 Enzymes are macromolecules that act as catalysts, speeding up chemical reactions by lowering activation energy without being consumed.
• 😀 The catalase enzyme is involved in breaking down hydrogen peroxide (H2O2) into water (H2O) and oxygen (O2).
• 😀 The experiment demonstrates how temperature and pH affect the activity of the catalase enzyme.
• 😀 Liver extract is used in the experiment because it contains high amounts of catalase enzyme in the peroxisomes of liver cells.
• 😀 Bubbles in the reaction indicate the formation of water (H2O), and sparks show the production of oxygen (O2).
• 😀 The catalase enzyme works best at neutral pH (around pH 7) and room temperature (around 30°C).
• 😀 High temperatures can denature enzymes, reducing their ability to function properly.
• 😀 At cold temperatures, the enzyme activity is also reduced, but not as severely as at high temperatures.
• 😀 In an acidic environment (low pH), catalase enzyme activity is significantly hindered.
• 😀 In an alkaline environment (high pH), catalase enzyme activity is also reduced, but not as much as in an acidic environment.
• 😀 The ideal conditions for catalase activity are neutral pH (pH 7) and a room temperature of about 30°C for optimal breakdown of hydrogen peroxide.

Q & A

What is the purpose of the catalase enzyme practicum demonstrated in the video?

The purpose is to demonstrate how temperature and pH influence the catalase enzyme's ability to break down hydrogen peroxide (H2O2) into harmless water (H2O) and oxygen (O2).

What are enzymes and how do they function?

Enzymes are macromolecules that act as catalysts in biochemical reactions. They accelerate reactions by lowering the activation energy required, without being consumed in the process.

What factors influence the activity of enzymes?

Factors that influence enzyme activity include temperature, pH, enzyme concentration, and the presence of inhibitors or binding agents.

Why was liver extract chosen for the catalase enzyme practicum?

Liver extract was used because the liver contains a high concentration of peroxisomes, which store the catalase enzyme that breaks down hydrogen peroxide.

What is the role of catalase enzyme in the body?

Catalase enzyme neutralizes hydrogen peroxide, a harmful by-product of metabolism, by converting it into water and oxygen, which are safe for the body.

What did the presence of bubbles indicate during the practicum?

The formation of bubbles indicated the breakdown of hydrogen peroxide into water and oxygen, a sign that the catalase enzyme was active.

What does the appearance of sparks when a fire is introduced to the mixture signify?

The appearance of sparks confirmed the presence of oxygen gas, which is produced when hydrogen peroxide is broken down by the catalase enzyme.

What was the outcome when the liver extract was exposed to an acidic environment?

In the acidic environment, fewer bubbles were produced, and no sparks appeared, showing that the catalase enzyme did not work optimally at an acidic pH.

How did the catalase enzyme perform in a cold environment?

In the cold environment (refrigerated liver extract), the enzyme produced fewer bubbles and only a small spark, indicating that the enzyme's activity is reduced at low temperatures.

What happens to the catalase enzyme at high temperatures?

At high temperatures, the enzyme's activity is diminished because the protein structure of the catalase enzyme is denatured, rendering it less effective at breaking down hydrogen peroxide.

What can be concluded about the optimal conditions for the catalase enzyme?

The catalase enzyme works best at a neutral pH (pH 7) and at room temperature (around 30°C), where it can efficiently break down hydrogen peroxide into water and oxygen.