The Ig fold can be described as a

The Ig fold can be described as a

A) globular fold composed of a helices.
B) a globular fold composed of a four helix bundle.
C) a globular fold composed of a ß sandwich.
D) a globular fold composed of ß barrel.
E) a coiled-coil.


Answer: C) a globular fold composed of a ß sandwich.

Which statement about antigen-binding sites in antibodies is false?

Which statement about antigen-binding sites in antibodies is false?

A) An antigen-binding site on an IgG is formed by the amino-terminal ~110 amino acids of a light chain and the amino terminal ~110 amino acids of a heavy chain.
B) An antigen-binding site on an IgG is formed by the variable region of a light chain and the variable region of a heavy chain.
C) The antigen-binding site is composed of two Ig folds.
D) Antigen-binding specificity is determined by the sequences of the hypervariable sequences in both the light chain and the heavy chain.
E) Antigen binding specificity is determined exclusively by the sequences in the carboxy- terminal ~110 amino acids in the light chain and the heavy chain.


Answer: E) Antigen binding specificity is determined exclusively by the sequences in the carboxy- terminal ~110 amino acids in the light chain and the heavy chain.

Fab fragments can be generated by

Fab fragments can be generated by

A) reduction of IgG molecules.
B) oxidation of IgG molecules.
C) limited digestion of IgG molecules with papain.
D) combining two light chains.
E) combining two heavy chains.


Answer: C) limited digestion of IgG molecules with papain.

How many antigen-binding sites are present on an IgM molecule?

How many antigen-binding sites are present on an IgM molecule? 

A) 2
B) 4
C) 10
D) 16
E) 25


Answer: C) 10