Alzheimer’s is a form of dementia which happens due to the deposition of amyloid beta (Aß). This happen in neural juncture of brain. Mad cow is a fatal neurodegenative disease caused in cattles due to a misfolded protein called Prions. Sickle-cell disease is a recessive genetic blood disorder. It causes abnormal, rigid, sickle shape of red blood cells due to mutation of the haemoglobin gene. Swine flu is a infection caused by various types of swine influenza virus. The known SIV strains include influenza C and the sub-types of influenza A known as H1N1, H1N2, H3N1, H3N2 and H2N3.

Correct Option: A

Alzheimer’s is a form of dementia which happens due to the deposition of amyloid beta (Aß). This happen in neural juncture of brain. Mad cow is a fatal neurodegenative disease caused in cattles due to a misfolded protein called Prions. Sickle-cell disease is a recessive genetic blood disorder. It causes abnormal, rigid, sickle shape of red blood cells due to mutation of the haemoglobin gene. Swine flu is a infection caused by various types of swine influenza virus. The known SIV strains include influenza C and the sub-types of influenza A known as H1N1, H1N2, H3N1, H3N2 and H2N3.

Immunoglobulin M, or IgM for short, is a basic antibody that is produced by B cells. IgM is by far the physically largest antibody in the human circulatory system. It is the first antibody to appear in response to initial exposure to antigen. The spleen is the major site of specific IgM production.the same time because the large size of most antigens hinders binding to nearby sites.

Correct Option: C

Immunoglobulin M, or IgM for short, is a basic antibody that is produced by B cells. IgM is by far the physically largest antibody in the human circulatory system. It is the first antibody to appear in response to initial exposure to antigen. The spleen is the major site of specific IgM production.the same time because the large size of most antigens hinders binding to nearby sites.

Hepatitis A virus (HAV), an atypical Picornaviridae that causes acute hepatitis in humans, usurps the HAV cellular receptor 1 (HAVCR1) to infect cells. HAVCR1 is a class 1 integral membrane glycoprotein that contains two extracellular domains: a virus-binding immunoglobulin-like (IgV) domain and a mucin-like domain that extends the IgV from the cell membrane. One of the early hallmarks of HIV infection is the impairment of a variety of CD4+ T-cell functions including T-cell colony formation, autologous mixed lymphocyte reactions, expression of interleukin-2 (IL-2) receptors, and IL-2 production. The nicotinic acetylcholine receptor (nAChR) is the first identified receptor for rabies virus. Rabies virus antigen was detected at sites coincident with nAChR. The nicotinic acetylcholine receptor (nAchR) is located at the postsynaptic muscle membrane. Heparan sulfate is a ubiquitously distributed polysulfated polysaccharide that is involved in the initial step of herpes simplex virus type 1 (HSV-1) infection. The virus interacts with cell-surface heparan sulfate to facilitate host-cell attachment and entry. 3-O-Sulfonated heparan sulfate has been found to function as an HSV-1 entry receptor.

Correct Option: C

Hepatitis A virus (HAV), an atypical Picornaviridae that causes acute hepatitis in humans, usurps the HAV cellular receptor 1 (HAVCR1) to infect cells. HAVCR1 is a class 1 integral membrane glycoprotein that contains two extracellular domains: a virus-binding immunoglobulin-like (IgV) domain and a mucin-like domain that extends the IgV from the cell membrane. One of the early hallmarks of HIV infection is the impairment of a variety of CD4+ T-cell functions including T-cell colony formation, autologous mixed lymphocyte reactions, expression of interleukin-2 (IL-2) receptors, and IL-2 production. The nicotinic acetylcholine receptor (nAChR) is the first identified receptor for rabies virus. Rabies virus antigen was detected at sites coincident with nAChR. The nicotinic acetylcholine receptor (nAchR) is located at the postsynaptic muscle membrane. Heparan sulfate is a ubiquitously distributed polysulfated polysaccharide that is involved in the initial step of herpes simplex virus type 1 (HSV-1) infection. The virus interacts with cell-surface heparan sulfate to facilitate host-cell attachment and entry. 3-O-Sulfonated heparan sulfate has been found to function as an HSV-1 entry receptor.

Although similar to Class I, the MHC Class II molecule is composed of two membrane spanning proteins. Each chain is approximately 30 kDa in size, and made of two globular domains. The domains are named α-1, α-2, β-1 and β-2. The two regions farthest from the membrane are α-1 and β-1. The two chains associate without covalent bonds. The MHC molecules ability to present a wide range of antigenic peptides for T cell recognition requires a compromise between broad specificity and high affinity. Class II molecules are dimers consisting of an α and β polypeptide chain. Each chain contains an immunoglobulin like region, next to the cell membrane. The antigen binding cleft, composed of two α-helices above a β-pleated sheet, specifically specifically binds short peptides, about 15 to 24 residues long. The amino acid sequence around the binding site, which specifies the antigen binding properties, is the most variable site in the MHC molecule.

Correct Option: C

Although similar to Class I, the MHC Class II molecule is composed of two membrane spanning proteins. Each chain is approximately 30 kDa in size, and made of two globular domains. The domains are named α-1, α-2, β-1 and β-2. The two regions farthest from the membrane are α-1 and β-1. The two chains associate without covalent bonds. The MHC molecules ability to present a wide range of antigenic peptides for T cell recognition requires a compromise between broad specificity and high affinity. Class II molecules are dimers consisting of an α and β polypeptide chain. Each chain contains an immunoglobulin like region, next to the cell membrane. The antigen binding cleft, composed of two α-helices above a β-pleated sheet, specifically specifically binds short peptides, about 15 to 24 residues long. The amino acid sequence around the binding site, which specifies the antigen binding properties, is the most variable site in the MHC molecule.

The sequence of oligosaccharides determines whether the antigen is A, B, or A1. The ABO blood group antigens are attached to oligosaccharide chains that project above the RBC surface. These chains are attached to proteins and lipids that lie in the RBC membrane. The ABO locus has three main allelic forms: A, B, and O. The A allele encodes a glycosyltransferase that produces the A antigen (N-acetylgalactosamine is its immunodominant sugar), and the B allele encodes a glycosyltransferase that creates the B
antigen (D-galactose is its immunodominant sugar). The O allele encodes an enzyme with no function, and therefore neither A or B antigen is produced, leaving the underlying precursor (the H antigen) unchanged. These antigens are incorporated into one of four types of oligosaccharide chain, type 2 being the most common in the antigen-carrying molecules in RBC membranes. Thus, in ABO system of blood grouping, the antigenic determinants are of carbohydrate origin.

Correct Option: B

The sequence of oligosaccharides determines whether the antigen is A, B, or A1. The ABO blood group antigens are attached to oligosaccharide chains that project above the RBC surface. These chains are attached to proteins and lipids that lie in the RBC membrane. The ABO locus has three main allelic forms: A, B, and O. The A allele encodes a glycosyltransferase that produces the A antigen (N-acetylgalactosamine is its immunodominant sugar), and the B allele encodes a glycosyltransferase that creates the B
antigen (D-galactose is its immunodominant sugar). The O allele encodes an enzyme with no function, and therefore neither A or B antigen is produced, leaving the underlying precursor (the H antigen) unchanged. These antigens are incorporated into one of four types of oligosaccharide chain, type 2 being the most common in the antigen-carrying molecules in RBC membranes. Thus, in ABO system of blood grouping, the antigenic determinants are of carbohydrate origin.