Which of the following statements pertaining to protein digestion and absorption is FALSE?
The majority of amino acids and peptides are absorbed in the upper portion of the small intestine.
Protein can enter the GI tract via ingestion or via secretion as enzymes or mucus
Proteins are absorbed as small peptides or amino acids via secondary active transport (co-transported with sodium)
Proteins are broken down by trypsin and chymotrypsin in the stomach, and peptin in the small intestine
i think its between the 2 and 3rd one
The statement "Proteins are broken down by trypsin and chymotrypsin in the stomach, and peptin in the small intestine" is FALSE.
In the stomach, proteins are initially broken down by the enzyme pepsin, not "peptin." Trypsin and chymotrypsin are pancreatic enzymes that are released in the small intestine and play a role in further breaking down proteins into smaller peptides and amino acids.
To determine which of the statements is FALSE, we need to evaluate the accuracy of each statement and eliminate the incorrect one.
Statement 1: "The majority of amino acids and peptides are absorbed in the upper portion of the small intestine."
This statement is true. The majority of protein digestion and absorption occurs in the small intestine, particularly in the upper portion called the duodenum. Proteins are broken down into smaller peptides and amino acids during digestion and then absorbed into the bloodstream.
Statement 2: "Protein can enter the GI tract via ingestion or via secretion as enzymes or mucus."
This statement is also true. Protein can enter the gastrointestinal (GI) tract through ingestion as part of the diet, but it can also be secreted into the GI tract as enzymes or mucus. Enzymes such as pepsin in the stomach or pancreatic enzymes in the small intestine are examples of proteins secreted into the GI tract.
Statement 3: "Proteins are absorbed as small peptides or amino acids via secondary active transport (co-transported with sodium)."
This statement is true. Proteins are broken down into smaller peptides and amino acids during digestion. These smaller molecules are then absorbed into the epithelial cells lining the small intestine. The absorption occurs through secondary active transport, which involves co-transporting these molecules along with sodium ions.
Statement 4: "Proteins are broken down by trypsin and chymotrypsin in the stomach and peptin in the small intestine."
This statement is FALSE. The primary protein digestion occurs in the stomach with the help of an enzyme called pepsin, which breaks down proteins into smaller polypeptides. Trypsin and chymotrypsin are pancreatic enzymes that are activated in the small intestine and further break down these polypeptides into smaller peptides and amino acids.
Therefore, the FALSE statement is: "Proteins are broken down by trypsin and chymotrypsin in the stomach, and peptin in the small intestine."