Multiple choice

One molecule of secretory IgA can at most bind to _____.

  1. 10 molecules of Ag

  2. 4 molecules of Ag

  3. 2 molecules of Ag

  4. 1 molecules of Ag

  5. 5 molecules of Ag
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

IgA is a dimer where 2 four-chain units are held together by the J chain through disulfide bridges. Each four chain unit has 2(paratopes) antigen binding sites. Thus 2 four chain unit is capable of binding 4 Ag molecules.

Keep practicing — related questions