EXERCISES, LESSON 2
INSTRUCTIONS: Answer the following items by completing the statement or by writing
the answer in the space provided.
After you have completed all of these items, turn to "Solutions to Exercises" at the
end of the lesson and check your answers with the solutions.
An antigen is traditionally defined as any substance that will cause production of
a________s and which reacts specifically with those a________s. This term,
however, is i________e because it emphasizes the production of
immunoglobulins. Therefore, the term i_________n was introduced to include
other biological processes, such as proliferation of l_________s and synthesis of
r_____tion m_______les which can specifically combine with the inducing
a________n. Antigens are macro_____s that possess a high degree of internal
chemical c_____ty. They are soluble or easily s____zed by p_____c cells of the
animal and are foreign to the animal.
A hapten is defined as a small m_____e which by itself cannot stimulate a_____y
s_____s but will combine with the a_____y once formed. When the hapten is
conjugated to a protein molecule called a c_____r, it can elicit an immune
The capacity to provoke a specific immune response is called i_____city. The
capacity to react with the products of the specific immune response is called
a______y. Substances that are immunogenic are always a____c, but antigens
are not necessarily i_____c.
The greater the m_____r w_____t of a substance, the more likely it is to function
as an antigen. Immunogenicity increases with str_____l c_____y. Poor antigens
often consist of molecules that are i_____ble in body fluids and which cannot be
converted to a s_____e form by tissue e_____s.
A substance not recognized as belonging to or being a part of the body is said to
be a f_____n substance. This characteristic is f_____ness.
Some host-related factors in immunogenicity are called no_____c f____s. These
host-related factors include g_____c m_____p, a_____e, and host e_____l and
n_____l status. Existing disease in the host may alter the capability for i_____e