Biology Questions and Answers

(Greg DeLong) #1

Biology Questions and Answers


lymphocytes. T lymphocytes


differentiate into thrcytotoxic T lymphocytesee main typ (cytotoxices: T (^)
cell), helper T lymphocytes (helper cell)
and suppressor T cytotoxic cells are the effectors olymphocytes. Thef the (^)
system, i.e., they directly attack other
cells recognizfungi cells, cellsed as foreign (for exam infected by virus, ple,
neoplastic cells, graft cells, etc.). The
helper cells and the suppressor Tlymphocytes act as regulators of the (^)
system releasing substances that
respectively stimulate animmune action of T and B lymd inhibit thphocytes.e (^)
After the primary memory T lymphocytesimmun also remain e response (^) in
the circulation to provide faster and
more effective reaction infections. in case of future



  1. What are the antigen-
    presenting cells of the
    immune system?


The antigen-presenting cimmune system, also known as APCells of the (^)
cells, are cells that do phagocytosis and
digestion of foreign (to thmicroorganisms and later ee body)xpose (^)
antigens derived from these
microortheir plasma mganismsembrane. These in the outer sid e of
processeby lymphocytesd antigens are then recognized that activate the
immune response. Several types of
cells, like tantigen-presentinhe macrog cells.phages, can act as



  1. What are passive and
    active immunization?
    According to the duration of
    the protection how do these
    types of immunization differ?
    Active immuantigen penetrates the body triggeringnization is that in which an
    the primary immune response and the
    production oantibodies that provide faster anf memory lymphocytesd more and
    effective immune defense in future
    infections bimmunization is that in y the same awhichntigen. Passive
    immunoglobulins against an antigen are


inoculated protection iin the body to providen case the body becomes (^)
infected by the antigen.
Active immunization tends to be longer
lasting thain the active type as wn passive immunization ell as antibodies,since
specific memory lymphocytes remain in
the circulation. Iimmunization the duration n the passiveof the (^)
protection is that of the duration of the
antibodies in the circulation.



  1. Why is maternal milk
    important for the immune
    protection of the baby?
    Besides being nutritionally important,


maternal milkdefense of the baby agai participates in tnst infectioushe (^)
agents. Soon after delivery the mother
produces a mcolostrum that is rich ore fluid milk calledin
immunoglobulins (antiboantibodies are not absorbed by thedies). These
baby’s circulation but they cover the
internal surthus attackingface of the baby’s bowels possible antigens and
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