Which of the following enzyme helps in digestion of fat?

Appeared in: RUHS, Jaipur, PB B.Sc Nursing Entrance-2023

Explanation

Lipase is the primary enzyme responsible for the hydrolysis (digestion) of dietary fats, specifically triglycerides.
It is secreted in large quantities by the pancreas (pancreatic lipase) and acts in the duodenum (the first part of the small intestine).
Lipase breaks down triglycerides into free fatty acids and 2-monoglycerides, which can then be absorbed by the intestinal cells.
The action of lipase is greatly enhanced by bile salts, which emulsify fats, increasing the surface area for the enzyme to work on.

Option A: Amylase is an enzyme that digests carbohydrates (starches), not fats. It breaks down complex carbohydrates into simpler sugars like maltose.
Option C: Enterokinase is not a digestive enzyme in the traditional sense; it is an activating enzyme. Its function is to convert the inactive zymogen, trypsinogen, into its active form, trypsin.
Option D: Trypsin is a proteolytic enzyme (a protease), meaning it is responsible for the digestion of proteins, not fats. It breaks down large protein molecules into smaller peptides.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Digestive Enzymes and their Functions as background academic context rather than a clinical decision trigger.
Measuring serum lipase and amylase levels is a cornerstone in diagnosing acute pancreatitis. When the pancreas is inflamed, these enzymes leak into the bloodstream, causing their levels to rise significantly.
Lipase is considered more specific to the pancreas than amylase and its levels remain elevated for a longer period, making it a more reliable diagnostic marker for pancreatic damage.
In conditions of pancreatic insufficiency (e.g., chronic pancreatitis, cystic fibrosis), inadequate lipase secretion leads to fat malabsorption, resulting in steatorrhea (fatty, foul-smelling stools). Treatment involves pancreatic enzyme replacement therapy (PERT).

How to Approach the Question

This is a factual recall question testing knowledge of basic physiology, specifically the function of digestive enzymes.
Identify the core of the question: which enzyme digests 'fat'.
Systematically review the function of each enzyme listed in the options.
Recall or deduce that 'lipo-' or 'lipid' relates to fats. This makes 'Lipase' a strong candidate.
Confirm the functions of the other enzymes: Amylase for carbohydrates, Trypsin for proteins, and Enterokinase as an activator for trypsinogen.
Select the enzyme that matches the substrate (fat) mentioned in the question.

Concept Tested & Keywords

QlDJ8l6sj8Y0RRZ1Eo87ie

E6 Physiology Guyton 4SAE Part 2A p. 202-204

E6 Physiology Ganong 27e Vol 2 Part 1 p. 30-32

E6 Medicine Harrison 22e Part 2 p. 647-649

Practise the full RUHS, Jaipur, PB B.Sc Nursing Entrance-2023

Attempt every question from this paper in a timed mock, then review the full solution for each one.