Dipeptide Definition, Formation and Structure Quiz

Explanation
A dipeptide is a molecule that consists of two amino acids joined together by a peptide bond. Therefore, the correct answer is "2 amino acids" because a dipeptide is specifically derived from the combination of two amino acids.

Explanation
Aspartame is a dipeptide because it is composed of two amino acids, aspartic acid and phenylalanine, joined together by a peptide bond. It is commonly used as an artificial sweetener in various food and beverage products.

Explanation
Aspartame is a type of artificial sweetener. It is commonly used as a sugar substitute in various food and drink products. It is known for its intense sweetness, which makes it a popular choice for those looking to reduce their sugar intake. Aspartame is not an antidepressant or a painkiller, so the correct answer is artificial sweetener.

Explanation
Homoanserine is the correct answer because it is a dipeptide that is found in the brain and muscles of mammals. It is formed by the combination of two amino acids, homoserine and alanine. This dipeptide plays a role in various physiological processes in the body and is involved in neurotransmission and muscle function.

Explanation
G-cells are the cells in the stomach that are activated by dipeptides to secrete gastrin. Gastrin is a hormone that plays a crucial role in regulating the secretion of gastric acid and the motility of the stomach. When dipeptides are present in the stomach, they stimulate G-cells to release gastrin, which then acts on the parietal cells to increase the production of gastric acid. This acid helps in the digestion of proteins and other nutrients in the stomach. Therefore, G-cells are responsible for the secretion of gastrin in response to dipeptides.

Explanation
Diketopiperazines are formed as side products in peptide synthesis. Diketopiperazines are cyclic dipeptides that can be produced when two amino acids react to form a peptide bond, but the reaction is incomplete. These side products can be formed due to various factors such as reaction conditions, steric hindrance, or the presence of impurities. Diketopiperazines are commonly observed in peptide synthesis and their presence can affect the yield and purity of the desired peptide product.

Explanation
Polypeptides are long chains of amino acids bonded together, and they can be broken down into smaller units called dipeptides. Therefore, it is logical to conclude that dipeptides are produced from polypeptides. Amino acids are the building blocks of both polypeptides and proteins, but they are not directly involved in the production of dipeptides. Oligopeptides are short chains of amino acids, but they are not specifically mentioned in relation to the production of dipeptides. Nucleic acids, such as DNA and RNA, are not directly involved in the production of dipeptides.

Explanation
The dipeptide found in the skeletal muscles and brains of mammals is Kyotorphin. Kyotorphin is a naturally occurring dipeptide composed of L-tyrosine and L-arginine. It has been identified in the central nervous system, including the brains of mammals, and is also present in skeletal muscles. Kyotorphin is known for its potential role in pain modulation and has been studied for its analgesic (pain-relieving) properties.

Explanation
Kyotorphin is a neuroactive dipeptide. A dipeptide is a molecule composed of two amino acids joined together by a peptide bond. Kyotorphin is a specific dipeptide that has been found to have neuroactive properties, meaning it can affect the nervous system. It has been studied for its potential analgesic and neuroprotective effects, making it a relevant option in the context of neuroactive dipeptides. Barettine, Glorin, and Xenortide are not known to have neuroactive properties.

Explanation
Glorin is the correct answer because it is a chemotactic dipeptide for the slime-mould Polysphondylium violaceum. This means that Glorin acts as a signaling molecule that attracts the slime-mould towards it. It is likely that Polysphondylium violaceum has specific receptors that recognize and respond to Glorin, causing the slime-mould to move towards the source of Glorin. The other options, Kyotorphin, Xenortide, and Carosine, are not chemotactic dipeptides for Polysphondylium violaceum.