Liver and Catalase makeup lab video

Summary

The video script outlines a scientific experiment exploring the enzyme catalase's activity in liver at varying conditions. It involves measuring hydrogen peroxide and adding liver to test tubes to observe reactions. The experiment tests the reusability of catalase, the impact of heat and cold on enzyme activity, and the effects of pH on its function. Observations include bubble formation indicating reactions, with varying intensity based on the treatment of liver and peroxide.

Takeaways

• 🧪 The experiment involves measuring and observing the reaction of hydrogen peroxide with liver tissue in test tubes.
• 🔬 Hydrogen peroxide is measured in 2 milliliters increments using a graduated cylinder for each test tube.
• 🐂 Freshly cut liver pieces are used as a source of the enzyme catalase, which reacts with hydrogen peroxide.
• 📝 Test tubes are labeled and observations are recorded, such as the formation of bubbles and changes in temperature.
• 🌡️ The experiment includes testing the effect of temperature on enzyme activity by heating and chilling liver samples.
• ♨️ A boiled liver sample shows reduced enzyme activity, indicated by minimal bubble formation.
• ❄️ A chilled liver sample maintains a high rate of reaction, suggesting that cold does not significantly inhibit catalase.
• 🔄 The experiment demonstrates that the enzyme catalase is reusable, as it continues to produce bubbles even after the first use.
• 🌐 The pH of the solution affects enzyme activity, with acidic conditions inhibiting the reaction, as seen in test tube five.
• 🌿 Alkaline conditions, on the other hand, do not seem to hinder the enzyme's activity, as evidenced by the bubbles in test tube six.

Q & A

What substance is being measured at the beginning of the experiment?

The substance being measured at the beginning is hydrogen peroxide, specifically 2 milliliters.

What happens when hydrogen peroxide is added to the liver in test tube number 1?

When hydrogen peroxide is added to the liver in test tube number 1, bubbles form and rise almost all the way to the top of the test tube, indicating a chemical reaction.

Why does the bottom of the test tube feel warmer after adding hydrogen peroxide to the liver?

The bottom of the test tube feels warmer because the reaction between hydrogen peroxide and the catalase enzyme in the liver is exothermic, meaning it releases heat.

What is the purpose of transferring the liquid from test tube number 1 to test tube number 2?

The purpose of transferring the liquid is to see if the catalase enzyme in the liver has already broken down the hydrogen peroxide, and whether the liquid can still cause a reaction with a fresh piece of liver.

What is observed when a fresh piece of liver is added to the liquid in test tube number 2?

No reaction occurs when a fresh piece of liver is added to the liquid in test tube number 2, indicating that the hydrogen peroxide has already been broken down by the catalase enzyme.

Is catalase reusable, based on the results from test tube number 1?

Yes, catalase is reusable. After adding fresh hydrogen peroxide to the liver in test tube number 1, more bubbles form, demonstrating that the enzyme can catalyze multiple reactions.

What effect does heating have on enzyme activity, as demonstrated in test tube number 3?

Heating the liver in test tube number 3 decreases enzyme activity. After the liver is heated and hydrogen peroxide is added, very few bubbles form, indicating a loss of enzyme function due to heat.

What is observed when cold liver and chilled hydrogen peroxide are used in test tube number 4?

Despite the cold temperature of the liver and hydrogen peroxide, there is still a strong reaction in test tube number 4, with bubbles forming almost to the same height as in previous tests.

How does an acidic solution affect enzyme activity in test tube number 5?

In test tube number 5, liver exposed to an acidic solution shows no reaction with hydrogen peroxide, indicating that the acidic environment inhibits the catalase enzyme activity.

How does an alkaline solution affect enzyme activity in test tube number 6?

In test tube number 6, liver exposed to an alkaline solution produces a strong reaction with hydrogen peroxide, with bubbles forming almost to the top of the test tube, showing that enzyme activity is still effective in a basic environment.