Question

The digestive enzyme that hydrolyzes molecules of fats into fatty acids is known as (A) bile (B) lipase (C) amylase (D) protease (E) trypsin

Short answer

(B) Lipase

Step-by-step solution

Understanding the role of Different enzymes

Understanding the roles of different digestive enzymes is vital. Amylase breaks down carbohydrates, protease breaks down proteins into peptides and amino acids, trypsin is a type of protease, and bile is not an enzyme but a compound that aids in the emulsification of fats.

Identify the Enzyme that Hydrolyzes Fat Molecules

The enzyme that specifically hydrolyzes (breaks down) molecules of fats into fatty acids is lipase. Therefore, lipase is the correct answer.

Key concepts

Lipase

Lipase is a crucial digestive enzyme produced by the pancreas and released into the small intestine. Its primary role is to break down fats (lipids) into smaller molecules like fatty acids and glycerol.
These smaller components can then be absorbed and utilized by the body as energy or for building other necessary compounds.

• Produced mainly in the pancreas.
• Released into the small intestine where it acts on dietary fats.
• Ensures fats are digested into absorbable units.

Understanding the role of lipase can help us see how the body efficiently breaks down and utilizes food. Without lipase, fats would pass through the digestive system undigested, leading to nutrient deficiencies and other health issues.

Enzyme Function

Enzymes are biological catalysts that speed up chemical reactions without being consumed in the process. They are essential for life as they allow metabolic processes to occur at rates fast enough to sustain life.
Each enzyme has a specific function and acts on specific substrates. For example, lipase specifically acts on fats.

• Speeds up chemical reactions.
• Not consumed in the reaction, so can be used repeatedly.
• Highly specific to their substrates.

By facilitating the breakdown of foods, enzymes like lipase, amylase, and protease ensure that the body receives the nutrients it needs efficiently.

Fat Digestion

Fat digestion begins in the mouth where enzymes in saliva start breaking down fats, but it mostly occurs in the small intestine. Lipase plays a central role here, managing the conversion of fats into fatty acids and glycerol.
The process is aided by bile, which emulsifies fats, creating a larger surface area for lipase to act upon. Without this emulsification, lipase would struggle to efficiently break down the fatty components.

• Majority of fat digestion happens in the small intestine.
• Lipase is the primary enzyme responsible for fat digestion.
• Bile aids in fat digestion by emulsifying fats.

Understanding how fats are digested can give insight into dietary choices, as the balance of enzymes and bile is crucial for healthy digestion.

AP Biology

AP Biology covers a broad range of topics, including the intricate processes of human physiology such as digestion. In the context of digestion, understanding how enzymes like lipase function is integral.
It's important for students to grasp how enzymes facilitate reactions essential for life.

• Explains the role of enzymes in digestion.
• Covers the biochemical pathways necessary for nutrient absorption.
• Provides a thorough understanding of the body's metabolic needs.

Learning about enzymes aligns with core objectives in AP Biology, allowing students to understand how organisms sustain themselves and convert food into energy.