Answer :
The secretion of bile and pancreatic juice is regulated by hormonal controls that ensure their proper release and function in the digestive process. The main hormones involved in this regulation are cholecystokinin (CCK) and secretin.
1. Cholecystokinin (CCK):
CCK is released by the mucosal cells of the small intestine in response to the presence of partially digested proteins and fats. Its primary actions are on the gallbladder and pancreas.
- Gallbladder: CCK stimulates the contraction of the gallbladder, leading to the release of stored bile into the common bile duct. Bile is essential for the digestion and absorption of dietary fats.
- Pancreas: CCK also stimulates the secretion of pancreatic enzymes, such as lipase, amylase, and proteases, from the acinar cells of the pancreas. These enzymes aid in the digestion of fats, carbohydrates, and proteins, respectively.
2. Secretin:
Secretin is released by the S cells in the duodenum in response to the acidic chyme entering from the stomach. It primarily acts on the pancreas and liver.
- Pancreas: Secretin stimulates the secretion of bicarbonate-rich pancreatic juice from the ductal cells of the pancreas. This alkaline fluid neutralizes the acidic chyme and provides an optimal pH for enzymatic digestion in the small intestine.
- Liver: Secretin stimulates the liver to produce and release bile into the bile ducts. Bile helps in the emulsification and absorption of dietary fats.
Both CCK and secretin act in coordination to ensure the appropriate release of bile and pancreatic juice, promoting efficient digestion and absorption of nutrients in the small intestine. The release of these hormones is triggered by specific stimuli related to the composition and pH of the chyme in the small intestine, ensuring that the digestive secretions are delivered when needed for effective digestion.
To know more about cholecystokinin click here:
https://brainly.com/question/2529312
#SPJ11