Write a short note on Digestion of protein
Answers
Answered by
5
The diet of human beings consists of different types of proteins. As a result of digestion, these protein ultimately get broken down into their simplest units namely amino acids. The digestion of the protein begins in the stomach and is completed in the small intestine. Proteins remain unaltered in the buccal cavity as the saliva does not have any protein digesting enzymes.
In the stomach, the food undergoes both mechanical and chemical digestion. During the periodic muscular contractions of the stomach, the food is churned and is mixed thoroughly with the gastric juice to form soft mass called bolus. The gastric juice in the stomach is secreted by the gastric glands.
This juice contains mucous hydrochloric acid and two proteases viz,, pepsinogen and prorennin. Hydrochloric acid does not digest the proteins but it activates the inactive enzymes pepsinogen and prorennin to pepsin and rennin. Hydrochloric acid also helps in maintaining the proper acidic pH for the action of the protein digesting enzymes.
The enzyme pepsin hydrolyses the large molecules of proteins into peptones and other polypeptides. Pepsin also can digest collagen. The enzyme rennin hydrolyses the milk protein casein into paracasein. Paracasein in the presence of calcium gets converted into calcium paracaseinate. Pepsin converts this also into peptones.
Further digestion of proteins takes place in the small intestine into which also flows the pancreatic juice. The semidigested proteins are acted upon by the pancreatic juice which consists of three protein digesting enzymes namely trypsin, chymotrypsin and carboxypeptidase. These enzymes are actually in their inactive stage but they become activated under the influence of the intestinal juice.
The enzyme trypsin breaks basic proteins into peptides. Chymotrypsin splits proteins into polypeptides and it also hydrolyses milk proteins. The car- boxypeptidases break the polypeptide chain into a number of dipeptides. The intestinal juice also contains two digestive proteases viz., amino peptidases and dipeptidases besides a non digestive protease called enterokinase.
Enterokinase activates the proteases in the pancreatic juice. The amino peptidases break up polypeptide chains to dipeptides and free aminoacids. The dipeptidases break up dipeptides into individual ammino acids. The amino acids are finally absorbed by the villi present in the inner wall of the small intestine.
In the stomach, the food undergoes both mechanical and chemical digestion. During the periodic muscular contractions of the stomach, the food is churned and is mixed thoroughly with the gastric juice to form soft mass called bolus. The gastric juice in the stomach is secreted by the gastric glands.
This juice contains mucous hydrochloric acid and two proteases viz,, pepsinogen and prorennin. Hydrochloric acid does not digest the proteins but it activates the inactive enzymes pepsinogen and prorennin to pepsin and rennin. Hydrochloric acid also helps in maintaining the proper acidic pH for the action of the protein digesting enzymes.
The enzyme pepsin hydrolyses the large molecules of proteins into peptones and other polypeptides. Pepsin also can digest collagen. The enzyme rennin hydrolyses the milk protein casein into paracasein. Paracasein in the presence of calcium gets converted into calcium paracaseinate. Pepsin converts this also into peptones.
Further digestion of proteins takes place in the small intestine into which also flows the pancreatic juice. The semidigested proteins are acted upon by the pancreatic juice which consists of three protein digesting enzymes namely trypsin, chymotrypsin and carboxypeptidase. These enzymes are actually in their inactive stage but they become activated under the influence of the intestinal juice.
The enzyme trypsin breaks basic proteins into peptides. Chymotrypsin splits proteins into polypeptides and it also hydrolyses milk proteins. The car- boxypeptidases break the polypeptide chain into a number of dipeptides. The intestinal juice also contains two digestive proteases viz., amino peptidases and dipeptidases besides a non digestive protease called enterokinase.
Enterokinase activates the proteases in the pancreatic juice. The amino peptidases break up polypeptide chains to dipeptides and free aminoacids. The dipeptidases break up dipeptides into individual ammino acids. The amino acids are finally absorbed by the villi present in the inner wall of the small intestine.
Answered by
4
Hey buddy here is ur answer !!
Protein Digestion
It's good to keep in mind that protein digestion is not as simple as eating an egg and magically getting amino acids. A large protein molecule breaks down via a few intermediate steps, in the stomach and in the small intestine, before it becomes the tiny amino acids. So, let's take a look at how proteins are broken down by your digestive system.
Protein digestion begins in the stomach with the action of an enzyme that we previously learned about called pepsin. Pepsin is the active protein-digesting enzyme of the stomach. When pepsin acts on the protein molecule, it breaks the bonds that hold the protein molecule together, called peptide bonds. So, you can think of pepsin as the enzyme that breaks peptide bonds. When these bonds are broken, you get chains of amino acids linked together called polypeptides. Since we know that the prefix 'poly' means 'many,' we can easily recall that a polypeptide is many amino acid units joined together. These polypeptides then move into your small intestine, where digestion will be completed by additional enzymes.
Pepsin is an enzyme in the stomach that breaks down the peptide bonds in protein.
Pepsin Breaks Peptide Bonds
In the small intestine, pancreatic enzymes that we previously learned about, called trypsin, chymotrypsin, and carboxypeptidase, really go to work breaking down the polypeptides. These enzymes enter the duodenum via the pancreatic duct. These pancreatic enzymes are helped by the brush border enzymes. We previously learned that the brush border enzymes are special enzymes found on the microvilli of the small intestine that complete digestion.
The peptide bonds holding the polypeptides together continue to be hydrolyzed, or broken down, and result in smaller units called peptides. Peptides are simply defined as two or more amino acids linked together. Enzymes continue to break down polypeptides and peptides into amino acids. Because amino acids are very small, they are able to be absorbed through the small intestine lining and into your bloodstream.
Hepatic Portal System
It's important to note that digested nutrients that leave the digestive tract take a detour to the liver before entering the general bloodstream. Your liver is an important organ, and this detour allows your liver to have first claim at nutrients coming from the digestive tract. It's almost like the liver is king and it gets first dibs at the good nutrients; then, when it takes its fill, the rest of the body has the leftovers.
Hey if this answer is helpful so plz make it as brainalist one plz .....
Protein Digestion
It's good to keep in mind that protein digestion is not as simple as eating an egg and magically getting amino acids. A large protein molecule breaks down via a few intermediate steps, in the stomach and in the small intestine, before it becomes the tiny amino acids. So, let's take a look at how proteins are broken down by your digestive system.
Protein digestion begins in the stomach with the action of an enzyme that we previously learned about called pepsin. Pepsin is the active protein-digesting enzyme of the stomach. When pepsin acts on the protein molecule, it breaks the bonds that hold the protein molecule together, called peptide bonds. So, you can think of pepsin as the enzyme that breaks peptide bonds. When these bonds are broken, you get chains of amino acids linked together called polypeptides. Since we know that the prefix 'poly' means 'many,' we can easily recall that a polypeptide is many amino acid units joined together. These polypeptides then move into your small intestine, where digestion will be completed by additional enzymes.
Pepsin is an enzyme in the stomach that breaks down the peptide bonds in protein.
Pepsin Breaks Peptide Bonds
In the small intestine, pancreatic enzymes that we previously learned about, called trypsin, chymotrypsin, and carboxypeptidase, really go to work breaking down the polypeptides. These enzymes enter the duodenum via the pancreatic duct. These pancreatic enzymes are helped by the brush border enzymes. We previously learned that the brush border enzymes are special enzymes found on the microvilli of the small intestine that complete digestion.
The peptide bonds holding the polypeptides together continue to be hydrolyzed, or broken down, and result in smaller units called peptides. Peptides are simply defined as two or more amino acids linked together. Enzymes continue to break down polypeptides and peptides into amino acids. Because amino acids are very small, they are able to be absorbed through the small intestine lining and into your bloodstream.
Hepatic Portal System
It's important to note that digested nutrients that leave the digestive tract take a detour to the liver before entering the general bloodstream. Your liver is an important organ, and this detour allows your liver to have first claim at nutrients coming from the digestive tract. It's almost like the liver is king and it gets first dibs at the good nutrients; then, when it takes its fill, the rest of the body has the leftovers.
Hey if this answer is helpful so plz make it as brainalist one plz .....
Similar questions