Which one of the following statements regarding bile secreted by liver is not correct?
Let's carefully examine each statement about bile, which is a digestive fluid produced by the liver.
Understanding Bile's Role in Digestion
Bile plays a crucial role in the digestion and absorption of fats in the small intestine. It is produced by the liver, stored in the gallbladder, and released into the duodenum.
We need to identify the statement that is incorrect regarding bile.
Analyzing Statements about Bile
Let's break down each statement:
- Statement 1: Bile contains enzymes for digestion of lipids.
Bile does not contain digestive enzymes. Digestion of lipids (fats) is carried out by enzymes called lipases (like pancreatic lipase), which are secreted by the pancreas into the small intestine. Bile salts in bile help break down large fat globules into smaller droplets (emulsification), increasing the surface area for lipases to act upon, but bile itself doesn't perform the enzymatic digestion.
Based on this, Statement 1 appears to be incorrect.
- Statement 2: Bile facilitates emulsification of fats.
This statement is correct. Bile salts are amphipathic molecules, meaning they have both hydrophilic (water-attracting) and hydrophobic (fat-attracting) parts. This property allows them to surround fat droplets, breaking them into smaller, more manageable particles. This process is called emulsification, and it significantly increases the surface area for lipase enzymes to digest the fats.
- Statement 3: Bile neutralizes the acidic pH of the food coming from stomach.
This statement is correct. The food leaving the stomach (called chyme) is highly acidic due to the presence of hydrochloric acid. Bile, along with pancreatic juice, contains bicarbonate ions (\(\text{HCO}_3^-\)). These bicarbonate ions help to neutralize the acidic chyme as it enters the duodenum, raising the pH. This alkaline environment is necessary for the optimal function of pancreatic and intestinal enzymes, including lipases.
- Statement 4: Bile makes the pH of the food alkaline and facilitates action of pancreatic enzymes.
This statement is also correct. As explained for Statement 3, bile contributes to making the environment in the small intestine alkaline. The alkaline pH (around 7.5-8.5) is essential for many pancreatic enzymes, such as pancreatic lipase, amylase, and proteases, to function efficiently and break down carbohydrates, proteins, and fats.
Comparing the statements, Statement 1 is the only one that is factually incorrect. Bile aids in fat digestion indirectly through emulsification and providing an alkaline environment, but it does not contain the enzymes that chemically break down lipids.
Summary of Bile Functions
| Function | Description |
|---|---|
| Emulsification of Fats | Bile salts break down large fat globules into smaller droplets. |
| Neutralization of Acid | Bile contains bicarbonate to neutralize acidic chyme from the stomach. |
| Making Environment Alkaline | Increases pH for optimal enzyme activity. |
| Excretion of Waste | Contains bilirubin and cholesterol for removal from the body. |
Therefore, the statement that is NOT correct regarding bile is that it contains enzymes for digestion of lipids.
Revision Table: Key Facts About Bile
| Aspect of Bile | Detail |
|---|---|
| Produced by | Liver |
| Stored in | Gallbladder |
| Released into | Duodenum (part of small intestine) |
| Composition | Bile salts, bile pigments (bilirubin), cholesterol, electrolytes, water, bicarbonate. |
| Contains Digestive Enzymes? | No, bile itself does NOT contain digestive enzymes. |
| Primary Role in Fat Digestion | Emulsification (physical breakdown) |
| Role in pH | Neutralizes acid, makes environment alkaline. |
| Function of Alkaline pH | Optimizes activity of pancreatic and intestinal enzymes. |
Additional Information on Digestion and Bile
Understanding the roles of different organs and secretions in digestion is key. While bile is produced by the liver, the pancreas is the primary source of digestive enzymes for fats, carbohydrates, and proteins. Pancreatic lipase is the enzyme responsible for hydrolyzing (chemically breaking down) triglycerides into fatty acids and monoglycerides. Bile's emulsifying action makes this enzymatic breakdown much more efficient by increasing the surface area exposed to lipase.
The journey of food involves different pH levels. The stomach is highly acidic (\(\text{pH } 1.5-3.5\)), which helps in protein digestion by pepsin and kills bacteria. As the chyme moves into the duodenum, the secretions from the pancreas and liver (bile) rapidly increase the pH to an alkaline range (\(\text{pH } 7.5-8.5\)), which is optimal for the enzymes working in the small intestine.
Similar Questions
Which one of the following is the correct sequence of organs that occur in the path of urine flow in human body?
Which one of the following is the Structure of a cardiac muscle cell ?
Which one of the following cell organelles mainly functions as storehouse of digestive enzymes?
The causal organism of dengue fever is a mosquito-borne virus which belongs to which one among the following categories?
Which of the following statements is/are correct about vaccination that provides
protection against an infectious disease?1. It blocks the entry of the infectious agent into body.
2. It produces antibodies against infection.
3. It kills the infectious agent when it enters in the body.
Select the correct answer using the code given below.
Which one of the following hormones contains peptide chain?
Which one of the following body parts/organs of the human body does not have smooth muscles?
Which of the following cells are destroyed by the HIV virus which results in the weakening of the immunity of a person?
Which one of the following hormones is essential for the uptake of glucose by cells in the human body?
Which of the following cells do not contain a nucleus?
1. Root hair cells
2. Red blood cells
3. Platelets
4. Monocytes
Select the correct answer using the code given below.
Important Questions from Human body
A resting person, usually has a pulse rate between ______ and ______ beats per minute
In humans, neck and head are joined by which joint ?
The human skeleton is composed of around ______ bones at birth.
Identify the disease that is not caused by virus.
Which one of the changes observed during adolescence is not associated with boys?
