Answer To: BIO212 Microbiology Exam 3 Essay Portion Your answer for each question should be a minimum of 250...
Robert answered on Dec 24 2021
Answer 1.
Isolation of antibodies against the measles virus from the body of a person (specifically
who is admitted in an emergency room due to any health complication) might be considered a
critical situation, but here it must be remembered that presence of such antibodies may not
always be linked with the infection caused by a pathogen. In fact, there is a high probability of
existence of these immune molecules in the individuals who are immunized against such disease
causing agents (Morell et al., 1983).
According to experts, it is also the principle underlying vaccination because, during this
process antigens (either killed, or attenuated) are introduced into the body of an individual with
the intention that, he could achieve resistance (immunity) against the pathogens. So anti-measles
antibodies can be recognized in those persons too who have been immunized against the measles
virus through vaccination for instance, individuals vaccinated by MMR vaccine (means vaccine
against Measles, Mumps, and Rubella) might also contain anti-measles antibodies. Besides, in a
few cases, infection with definite viruses like Rabies, Measles, and Ebola etc can be treated with
the help of antibodies directed in opposition to the causal viruses. In that condition too anti-
measles antibodies could be present into the blood of an individual (Marx et al., 2006).
Thus to affirm that a person is suffering from measles, further analysis is essential. This
can be performed with the help of specific tests involving RT-PCR in which presence of virus
into the body of patient can be detected with the assistance of respiratory (throat/nasopharyngeal
swabs) and urine samples of the patient. That's why, a patient should be quarantined only after
detection of such agent into his body via precise assessment otherwise, it’s not essential.
Answer 2.
Numerous research studies (based on unwell and fit persons) have confirmed that after
recovery from an illness, the quantity of antibodies linked with agent(s) responsible for infection
can get reduced into the body of an individual. Even after a definite period these may not be
found into the body, but the immune system can save such individuals from the succeeding
infections caused by same pathogen in an amazing manner. In fact, immune system can respond
in a quicker and better way (in comparison to primary infection) when it encounters the same
antigen subsequently. Such faster and superior immune response is well-known as secondary
response (Holyoake et al., 2002).
The clonal selection or clonal expansion theory puts in plain words how body comprises
an intrinsic capability to generate a vast variety of antibodies with diverse amino acid sequences
which can competently bind to a huge array of antigens. The fundamental principle of such
effectual immune reaction against secondary infection is that it reveals contribution of a large
number of antigen-specific cells renowned as memory cells (B and/or T cells) (Morell et al.,
1983).
During initial clonal expansion (means an immunological reaction in which lymphocytes
excited by antigen multiply and intensify the population of related cells), a small number of
progeny cells may not get developed into plasma cells. Instead, they form miniature lymphocytes
consisting of identical particular surface receptor (s) as present on their precursors. Besides,
clone-memory cells (other class of immune cells) can also persist for a short time even if the
antigen is no longer there. This perseverance comprises the memory of our immune system and
due to above cells, the subsequent infections by an antigen might be recognized in a quick
manner, and could lead towards a faster immense response by body against such encounters.
Answer 3.
Identification of antibodies against HIV (for instance, via ELISA) cannot be considered
AIDS since HIV may take several years for development of this disease after its infection. This
time period may vary according to the nutritional, hygienic, and immunological status of victim.
During this time frame, HIV can lead towards immuno deficiency through diverse ways for
instance; it may exhibit replication and thus can form several copies of it. Besides, it might get
evolved through mutation and recombination. As a consequence of above mechanisms, it may
learn how to avoid the reaction of immune system and thus can kill its prey in a slow, but steady
manner.
In fact, HIV can destroy the immune system through destruction of billions of immune
cells (like CD4+ T- cells) on a daily basis because of which, immune system's ability to renew
itself and/or fight against other infections can be damaged. Several techniques might be adopted
by HIV for this purpose for instance, it can perform this task via directly killing the CD4+ T-
cells with the help of budding process that may disintegrate the membrane of a cell and could
lead towards its death. Besides, it can exploit the immune cells for its own profits and thus can
damage the usual vital activities required for their survival. As a consequence of which, infected
cells may commit suicide through apoptosis (Diamond et al., 2005).
In addition to above, HIV can also adopt amazing ways to kill those innocent cells which
are not infected with it for instance, through binding with their surface because of which, these
can be destroyed by CD8(+)T -cells/ killer T- cells that may recognize antigen-antibody complex
formed on immune cells’ surface (mechanism is renowned as Antibody-Dependent Cellular
Cytotoxicity (ADCC)).
Over and above, immune precursor cells means the young immune cells that could not be
transformed into mature cells with particular immune functions might be damaged by HIV.
Ultimately, it can also destroy the lymphoid organs including bone marrow and thymus that play
a leading role in the production of immune cells. Even due to HIV infection, these organs may
lose their regeneration capability too as a consequence of which, immune system can get
suppressed further (Marx et al., 2006).
All above defined factors and/or reactions may be called responsible for the development
of AIDS that can be characterized via the deficiency of immunity into the body of HIV infected
person. Further, it must be remembered that merely formation of antibodies against a particular
pathogen cannot be called enough to consider an individual “immune”, but the immunity is
shaped by various molecules, cells, and organs that can be killed by HIV in a severe mode.
Answer 4.
Innate and Adaptive immunity both can be called “life-savers”. Cells/molecules linked
with them may also share the place of origin (like bone marrow) and residence (blood and
lymphatic tissue) still, a number of variations could be found between them in terms of structure
as well as functions. For example; innate immunity may be considered a non-specific immune
response whereas, adaptive immunity is specific by nature.
Moreover, innate immunity can be recognized in a person from the time of birth while
development of adaptive immunity depends on the exposure of antigen either through natural
mode, or in artificial manner. For instance, direct encounter with Vibrio cholerae because of
consumption of contaminated food can be considered natural way...