Question

Cholecystokinin (CCK) is a hormone that stimulates a. bile production. b. release of pancreatic enzymes. c. contraction of the gallbladder. d. both \(a\) and \(b\). e. both \(b\) and \(c\).

Short answer

Cholecystokinin (CCK) is a hormone that stimulates bile production, release of pancreatic enzymes, and contraction of the gallbladder. However, the given options (d) and (e) are both correct, as they are combinations of these functions. The question should be revised to have only one correct answer.

Step-by-step solution

Understanding Cholecystokinin (CCK) Functions

To solve this exercise, the first step is to memorize the functions of Cholecystokinin (CCK), a hormone which is typically released after eating. CCK's primary roles include the stimulation of bile production, pancreas enzymes release and gallbladder contraction. It is important to note that bile is produced by the liver and stored in the gallbladder, while the pancreatic enzymes are crucial for digestion.

Evaluating the Answers

The next step is to examine each answer option and determine which ones align with the known functions of CCK.

Evaluating Option a

Option (a) suggests that CCK stimulates bile production. This is accurate: one of the main functions of CCK is stimulating bile production.

Evaluating Option b

Option (b) states that CCK stimulates the release of pancreatic enzymes. This is also correct; releasing pancreatic enzymes is another primary function of CCK.

Evaluating Option c

Option (c) proposes that CCK stimulates gallbladder contraction. This is correct, as the gallbladder moves bile into the digestive tract under the influence of CCK.

Evaluating Option d

Option (d) suggests that both statements a and b are correct, which is true as we have confirmed that CCK indeed stimulates bile production and the release of pancreatic enzymes.

Evaluating Option e

Lastly, option (e) indicates that both statements b and c are correct. This is also true as CCK not only stimulates the release of pancreatic enzymes, but also causes gallbladder contractions.

Final Conclusion

Thus, based on our understanding of biology, we can say that options (a), (b) and (c) are all correct. Hence, options (d) and (e) are also correct as they are simply combinations of the first three. Therefore, the teacher should consider revising this question to ensure that there is only one correct answer.

Key concepts

Hormones

Hormones are vital chemicals released by glands in the body. They regulate various bodily functions and maintain homeostasis.
Cholecystokinin (CCK) is a specific hormone released by the small intestine. It plays a crucial role in digestion. The body releases it in response to eating, especially after consuming fats and proteins.
CCK communicates with several organs to coordinate digestion:

• Stimulates the pancreas
• Influences the gallbladder
• Affects bile production

These activities are essential for breaking down food and absorbing nutrients. Understanding CCK and its functions helps us appreciate how our bodies efficiently manage food digestion.

Bile Production

Bile plays a critical role in digestion, especially in fat breakdown. Though CCK stimulates processes related to bile, it's essential to clarify its role precisely.
Bile is produced continuously by the liver regardless of CCK presence. This fluid consists of bile acids, cholesterol, and waste products.
The primary function of bile is to emulsify fats, making them easier for digestive enzymes to act on. Without bile, fat digestion would be inefficient.

• Bile is crucial in neutralizing stomach acids.
• It aids in fat-soluble vitamin absorption.

While CCK does not directly stimulate bile production, it influences bile movement by affecting gallbladder contraction, an essential phase in fat digestion.

Pancreatic Enzymes

Pancreatic enzymes are essential for breaking down proteins, carbohydrates, and fats. CCK plays a prominent role in their release into the small intestine.
Upon eating, especially fatty meals, the small intestine releases CCK. This hormone signals the pancreas to secrete enzymes that facilitate nutrient breakdown.

• Proteases break down proteins.
• Lipases target fats.
• Amylases manage carbohydrates.

These enzymes work together to ensure efficient digestion and nutrient absorption. CCK is integral in this process, ensuring the right enzymes are available at the right time.

Gallbladder Contraction

The gallbladder is a small organ located beneath the liver. It stores bile produced by the liver.
When digestion requires bile, CCK springs into action, causing the gallbladder to contract. This contraction pushes bile through the bile ducts and into the small intestine, where it mixes with food.

• CCK ensures bile meets digestive needs.
• This process enhances fat digestion.

Without CCK-induced contractions, the bile would remain in the gallbladder, delaying the digestion of fats. Understanding this function highlights CCK's importance in the digestive process.