Which of the antibody classes is able to cross epithelial cells and is therefore present in breast milk?
A) IgM only
B) IgA only
C) IgG only
D) both IgG and IgM
E) both IgM and IgA
Ans: B) IgA only
You might also like to view...
What limits the size of a cell?
a. lack of building materials b. the size of the organism c. the relationship between the volume of the cell and its surface area d. the job it does e. the materials it has to exchange
Which of the following is(are) false regarding
B cells with antigen-MHC complexes? a. They are stimulated by helper T cells to secrete cytokines. b. Helper T cells signal them to divide and differentiate. c. On signals from the helper T cells, they produce clones with identical receptors. d. Once activated by signals from helper T cells, they produce IgG, IgA, or IgE immunoglobulins instead of membranebound IgM. e. All of these are true.
In which of these environments would you normally find prokaryotes?
A) An animal's intestinal tract B) Human skin C) A single drop of seawater D) A spoonful of soil E) All of the above
Plasmodium reproduces by binary fission
Indicate whether the statement is true or false