Question

Identify the immunoglobulins (i), (ii), (iii) and (iv) and select the correct option.

(i) It is only antibody that can cross placenta and confer immunity to foetus.

(ii) It is mediator in allergic reactions and activates histamine secreting cells.

(iii) It is the one that first activates in an initial attack of antigen.

(iv) It has role in activating and suppressing lymphocyte activity.

• A.
  $\begin{array}{c}\text{a)}\text{IgD}\\ \text{b)}\text{IgM}\\ \text{c)}\text{IgE}\\ \text{d)}\text{IgG}\end{array}$
• B.
  $\begin{array}{c}\text{a)}\text{IgG}\\ \text{b)}\text{IgE}\\ \text{c)}\text{IgM}\\ \text{d)}\text{IgD}\end{array}$
• C.
  $\begin{array}{c}\text{a)}\text{IgE}\\ \text{b)}\text{IgG}\\ \text{c)}\text{IgM}\\ \text{d)}\text{IgD}\end{array}$
• D.
  $\begin{array}{c}\text{a)}\text{IgG}\\ \text{b)}\text{IgM}\\ \text{c)}\text{IgE}\\ \text{d)}\text{IgD}\end{array}$

Answer 1

The correct option is B

$\begin{array}{c}\text{a)}\text{IgG}\\ \text{b)}\text{IgE}\\ \text{c)}\text{IgM}\\ \text{d)}\text{IgD}\end{array}$
(i) It is only antibody that can cross placenta and confer immunity to the foetus – IgG

(ii) It is mediator in allergic reactions and activates histamine secreting cells – IgE

(iii) It is the one that first activates in an initial attack of antigen – IgM

(iv) It has role in activating and suppressing lymphocyte activity – IgD