Immunoglobulins

Question 1

Immunoglobulins

Answer 1

Are Protein made by B cells and plasma cells (types of white
blood cells) which helps the body fight infection.
❑Immunoglobulins include a diverse group of proteins
(Globulins),
❑which have antibody activity.
❑They are synthesized and secreted by B Cells in response to
invasion of an antigens.

Question 2

What do immunoglobulins do

Answer 2

■ recognize and bind to a particular antigen with very
high
❑specificity.

  ❑Each antibody has atleast two identical sites that bind antigen: ❑Antigen binding sites.

  ❑Valence of an antibody: Number of antigen binding sites. Most are: ❑bivalent.

❑ found in serum and some tissue fluids.
❑is about 20% of total plasma
proteins.

Question 3

Structure of immunoglobulins

Answer 3

❑Monomer:is ‘Y’ shaped molecule
❑Has four polypeptide chains.
❑Two of the chains are large subunits called Heavy(H) Chains
❑The other two are small subunits called Light(L) Chains.

❑All four chains are joined by–S-S Linkages

Question 4

❑Variable(V)Regions:

Answer 4

Two sections at the end of Y’s arms.
Contain
antigen binding sites(Fab).
Identical on the same antibody, but vary
from one antibody to another.

Question 5

Constant Regions

Answer 5

Stem of monomer and lower parts of Y arm

Question 6

Fc Region

Answer 6

Stem of monomer only. important because they can bind to complement or cells

Question 7

Hinge region

Answer 7

When Both arms are linked to the stem by a flexible region