Problem 42 - A Complete Resource Book in Chemistry for JEE Main

Question

The enzyme which hydrolyses triglycerides to fatty acids and glycerol is called (a) pepsin (b) zymase (c) maltose (d) lipase

Step-by-Step Solution

Answer

The enzyme is lipase (option d).

Step 1: Understand the Question

The question asks about the specific enzyme responsible for breaking down triglycerides into fatty acids and glycerol in the body.

Step 2: Identify Key Terms and Concepts

Focus on the key terms: 'triglycerides', 'fatty acids', and 'glycerol'. These are types of lipids and their breakdown relates to lipid metabolism.

Step 3: Recall Enzymatic Functions

Recall that an enzyme is a biological catalyst that speeds up chemical reactions. Here, we need an enzyme that specifically breaks down lipids.

Step 4: Evaluate Each Option

Examine each option: - (a) Pepsin: An enzyme involved in breaking down proteins. - (b) Zymase: A complex of enzymes involved in glycolysis or fermentation, not in lipid metabolism. - (c) Maltose: Incorrect option as maltose is a sugar, not an enzyme. - (d) Lipase: An enzyme known to specifically break down fats or lipids, such as triglycerides, into fatty acids and glycerol.

Step 5: Select the Correct Option

The correct enzyme that hydrolyses triglycerides into fatty acids and glycerol is option (d) lipase.

Key Concepts

Lipid Metabolism

Lipid metabolism refers to the processes that involve the synthesis and degradation of lipids in cells. These processes are crucial for maintaining a balance of energy in the body.
Lipids, which are fats and oils, are excellent energy stores. They provide more energy per gram than carbohydrates or proteins, which makes them valuable for energy storage.
The breakdown of stored lipids involving triglycerides is key to energy supply. This process ensures that when the body needs energy, such as during fasting or exercise, it has a readily available supply.
Lipid metabolism pathways also play a role in synthesizing key biological molecules. Lipids involve the production of cholesterol and steroid hormones, which are vital for many physiological processes. Functions of lipid metabolism include:

• Energy provision and storage
• Production of signaling molecules
• Formation of cell membranes

Understanding lipid metabolism is important in the context of health. Imbalances can lead to metabolic disorders, like obesity or diabetes, highlighting the importance of managing lipid levels through diet and lifestyle.

Lipase

Lipase is an enzyme that plays a vital role in breaking down fats, specifically triglycerides, into their components - fatty acids and glycerol.
As an essential enzyme of the digestive system, lipase ensures that dietary fats are properly digested and absorbed in the intestines.
Lipase is produced mainly in the pancreas, although it is also secreted by the stomach and small intestine.
This enzyme works by catalyzing the hydrolysis of ester bonds in triglycerides, transforming them into free fatty acids and monoclycerides that can be absorbed through the intestinal wall. The activity of lipase is important in numerous physiological processes:

• Digestion of dietary fats
• Facilitating the absorption of fat-soluble vitamins like A, D, E, and K
• Assisting in the regulation of cholesterol levels

Any dysfunction in lipase secretion or activity can cause malabsorption issues, leading to nutritional deficiencies. Understanding the function and importance of lipase helps in grasping how the body efficiently utilizes dietary fats.

Hydrolysis of Triglycerides

The hydrolysis of triglycerides is an enzyme-mediated reaction wherein these lipid molecules are broken down into fatty acids and glycerol.
This process is crucial because it transforms stored fats into substances that the body can use for energy production and other functions.
Triglycerides, which consist of three fatty acids bound to a glycerol molecule, are the most common form of fat stored in the body.
Hydrolysis involves the breaking of these ester bonds, a process facilitated by enzymes like lipase, leading to the release of fatty acids and glycerol. Importance of triglyceride hydrolysis:

• Essential for retrieving stored energy during periods of energy need
• Allows the body to use fats when carbohydrates are not available
• Plays a role in maintaining balanced energy levels

An in-depth understanding of triglyceride hydrolysis can help understand broader metabolic pathways and how enzymes work together to maintain energy homeostasis in the body.