Biochem Glycoproteins

Heparin is produced by mast cells and is used as an anticoagulant. It prevents blood clotting by inhibiting the activity of certain clotting factors. This helps to prevent the formation of blood clots in the blood vessels, reducing the risk of complications such as deep vein thrombosis, pulmonary embolism, and stroke. Heparin is commonly used in medical settings to prevent blood clots during surgeries, dialysis, and in the treatment of certain medical conditions like heart attacks and deep vein thrombosis.

ER glycosylation refers to the process of adding sugar molecules to proteins in the endoplasmic reticulum (ER). This type of glycosylation occurs specifically on the side chain N (amino group) of asparagine residues in the protein sequence. Therefore, it is called N-glycosylation. O-glycosylation, on the other hand, refers to the addition of sugar molecules to the hydroxyl group of serine or threonine residues. Viral neuraminidase is an enzyme involved in the cleavage of sialic acid from glycoproteins and glycolipids. Therefore, the correct answer is N-glycosylation.

Erythrocytes, also known as red blood cells, have a lifespan of approximately 120 days. These cells play a crucial role in transporting oxygen throughout the body. Over time, they become worn out and are removed from circulation by the spleen and liver. The body constantly produces new erythrocytes to replace the old ones, ensuring a healthy supply of oxygen to tissues and organs.

Glycosaminoglycans (GAGs) are the heteropolysaccharides found in the basement membrane. These are long, linear chains of repeating disaccharide units that are heavily negatively charged. GAGs play a crucial role in maintaining the structural integrity and function of the basement membrane, which is a specialized extracellular matrix that provides support and acts as a barrier between different tissues. Thrombin is a protein involved in blood clotting, and endotoxin is a toxic component of the outer membrane of certain bacteria. Therefore, neither thrombin nor endotoxin are the correct answer for the name of the heteropolysaccharides in the basement membrane.

Glucose oxidase is an enzyme that converts glucose and oxygen into gluconolactone and H2O2. This enzyme is commonly used in various applications, such as in the food industry for measuring glucose levels and in medical diagnostics for measuring blood glucose levels. It catalyzes the oxidation of glucose, producing gluconolactone and hydrogen peroxide as byproducts. Therefore, glucose oxidase is the correct answer to the given question.

O-glycosylation is the correct answer because Golgi glycosylation refers to the addition of carbohydrate molecules to proteins at serine and threonine residues. This process is specifically known as O-glycosylation. N-glycosylation, on the other hand, occurs at asparagine residues and is a different type of glycosylation. Viral neuraminidase is not related to Golgi glycosylation. Therefore, the correct answer is O-glycosylation.

Proteoglycans are formed by the linkage of a carbohydrate chain to a protein core. This linkage occurs through a specific amino acid residue in the protein core. In the case of proteoglycans, the linkage occurs on the amino acid serine. Therefore, serine is the correct answer for the amino acid on which the linkage to form proteoglycans occurs.

Heparin is a medication that is commonly used as an anticoagulant to prevent blood clots. However, one of the potential side effects of heparin is thrombocytopenia, which is a condition characterized by a low platelet count in the blood. Platelets are necessary for blood clotting, so a decrease in platelet count can increase the risk of bleeding. Therefore, thrombocytopenia is a possible adverse effect of heparin treatment.

The correct answer is gram negative bacterial cell wall. Gram negative bacteria have a unique outer membrane that contains lipopolysaccharides (LPS) on their cell wall. LPS is a potent endotoxin that can trigger an excessive immune response, leading to septic shock. This condition occurs when the body's immune system overreacts to an infection, causing widespread inflammation and organ dysfunction. Gram positive bacterial cell walls do not contain LPS, so they are not responsible for septic shock. Plant cell walls are made of cellulose and are not related to septic shock.

Hyaluronic acid can be found in various parts of the body, including the synovial fluid of joints, the extracellular matrix of cartilage and tendons, the vitreous humor of the eye, and around the egg.

Proteoglycans are complex molecules composed of a core protein with attached glycosaminoglycan (GAG) chains. Chondroitin sulfate, dermatan sulfate, and keratin sulfate are all examples of glycosaminoglycans, and they are commonly found in various proteoglycans throughout the body. These proteoglycans play essential roles in connective tissues, providing structural support, hydration, and cushioning.

Viral neuraminidase is an enzyme that can remove sialic acid (neuraminic acid) residues. Sialic acid residues are commonly found on the surface of cells and play important roles in cell recognition and signaling. Viral neuraminidase is produced by certain viruses, such as influenza viruses, and helps the virus to release from infected cells by cleaving the sialic acid residues. This allows the virus to spread and infect other cells. N-glycosylation and O-glycosylation are different types of protein modifications that involve the addition of sugar molecules, but they do not specifically remove sialic acid residues. Therefore, the correct answer is viral neuraminidase.

Hb-A1C provides indications of plasma glucose levels. Hb-A1C is a form of hemoglobin that is used to measure the average blood sugar levels over a period of time. It reflects the amount of glucose that has been attached to hemoglobin in red blood cells. By measuring Hb-A1C levels, healthcare professionals can assess a person's long-term blood sugar control and diagnose or monitor diabetes.

Lectins are carbohydrate-binding proteins that have the ability to attach to specific sugar molecules on the surface of cells. In this case, the correct answer is "all of the above" because lectins can attach to herpes, H. pylori, diptheriotoxin, and pertussis toxin. Lectins play a role in various biological processes such as cell adhesion, immune response, and pathogen recognition.

Cephalosporins are beta-lactam antibiotics because they contain a beta-lactam ring in their chemical structure. This ring is responsible for the antibacterial activity of beta-lactam antibiotics by inhibiting the synthesis of the bacterial cell wall. Oseltamivir (Tamiflu) and zanamivir (Relenza) are not beta-lactam antibiotics, as they belong to a different class of drugs called neuraminidase inhibitors, which are used to treat influenza virus infections. Therefore, the correct answer is cephalosporins.

Dolichol phosphate is a lipid carrier that plays a crucial role in the synthesis and transport of glycoproteins. It acts as a carrier molecule for transferring sugar molecules from the cytoplasm to the endoplasmic reticulum, where they are added to proteins to form glycoproteins. This process is essential for the proper folding and functioning of many proteins. Therefore, dolichol phosphate is the correct answer as it is directly involved in the transport of lipids and sugars in the cell.

The Lipid A portion of the bacterial cell wall is referred to as endotoxin. Endotoxins are a type of toxin that is released from the cell wall of certain bacteria when they die or undergo lysis. Lipid A is the toxic component of the endotoxin and is responsible for inducing an inflammatory response in the body. Endotoxins can cause fever, shock, and other symptoms when they enter the bloodstream, and they play a significant role in the pathogenesis of bacterial infections.

Fusion inhibitor drugs are the correct answer because they specifically target the attachment of the herpes virus or HIV to the surface of cells. These drugs work by blocking the fusion of the viral envelope with the host cell membrane, preventing the virus from entering and infecting the cell. Penicillins and cephalosporins are antibiotics that are not effective against viruses, while oseltamivir (Tamiflu) and zanamivir (Relenza) are antiviral drugs used to treat influenza, not herpes or HIV.

The correct answer is B and C. Oseltamivir (Tamiflu) and zanamivir (Relenza) are drugs that inhibit viral neuraminidase. Neuraminidase is an enzyme found on the surface of the influenza virus, and it plays a crucial role in the release of new virus particles from infected cells. By inhibiting neuraminidase, these drugs prevent the spread of the virus within the body and reduce the severity and duration of influenza symptoms. Cephalosporins, on the other hand, are a class of antibiotics that do not have any effect on viral neuraminidase.

The correct answer is bacteria cell wall. Bacteria cell walls are held together by pentapeptide chains that have D-Ala-D-Ala. This unique structure is not found in plant cell walls or glycosaminoglycans. Therefore, the correct answer is bacteria cell wall.