Regarding epitopes for BCRs and/or for TCRs, indicate whether each statement below (a-e) is true. (5 pts) If the statement is only true for epitopes for BCRs--write (B) If the statement is only true for epitopes for TCRs--write (T) If the statement is true for epitopes for both BCRs and TCR--write (BT) If the statement is NOT true for either epitopes for BCRs or TCR--write (N) a. epitopes may consist of non-sequential amino acids b. epitopes are often from the interior of an antigen c. epitopes can be present in immunogens d. epitope binding to the antigen receptor obeys the 12/23 rule e. multiple identical epitopes may be present in a single antigen

a-B

b-N

c-BT

d-BT

e-BT

Explanation:

a. epitopes may consist of non-sequential amino acids >  B (is only true for epitopes for BCRs)

b. epitopes are often from the interior of an antigen > N (IS ONLY TRUE FOR EPITOPES FOR TCR)

c. epitopes can be present in immunogens  > BT (True for both TCR and BCRs )

d. epitope binding to the antigen receptor obeys the 12/23 rule > BT (True for both TCR and BCRs )

e. multiple identical epitopes may be present in a single antigen > BT (True for both TCR and BCRs )

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.

currents is the correct answer.