2025 |GUARANTEED ACCURATE
ANSWERS
One of the most important advances in surgery arrived near the end of
the nineteenth century. The British surgeon Joseph Lister hypothesized
that using techniques to sterilize surgical tools and clean the skin at the
site of the incision would reduce surgical site infections. Years later, Dr.
Lister wrote this:
"Nothing was formerly more striking in surgical experience than the
difference in the behavior of injuries according to whether the skin was
implicated or not. Thus, if the bones of the leg were broken and the skin
remained intact, the surgeon applied the necessary apparatus without any
other anxiety than that of maintaining a good position of the fragments,
although the internal injury to bones and soft parts might be very severe.
If, on the other hand, a wound of the skin was present, communicating
with the broken bones, although the damage might be in other respects
comparatively slight, the compound fractu - ACCURATE
ANSWERS✔✔ Epithelial barriers
Which of the cells below are tissue resident sentinel cells - ACCURATE
ANSWERS✔✔ mast cell, macrophage, dendritic cell
Which of the cells below are circulating blood cells that will enter tissue
in response to inflammation? (select two answers) - ACCURATE
ANSWERS✔✔ Neutrophils
,Monoctyes
Mast cell - ACCURATE ANSWERS✔✔ Cells that release chemicals
(such as histamine) that promote inflammation.
Neutrophil - ACCURATE ANSWERS✔✔ Most abundant leukocyte
Phagocyte that rapidly dies after ingesting microbe
macrophage - ACCURATE ANSWERS✔✔ Phagocyte that cleans up
apoptotic cells
When a monocyte moves into the tissues, it changes rapidly and
becomes a ____________ . - ACCURATE ANSWERS✔✔ macrophage
Leukocyte adhesion deficiency (LAD) is a genetic defect that leads to
recurrent infections in the tissue and severe problems with wound
healing. LAD patients also develop severe gingivitis (infections and
inflammation of the gums). In LAD, leukocyte migration into tissues is
severely impaired. All of these problems can be traced back to a genetic
defect. Of the genetic defects listed below, which is the most likely
cause of LAD? - ACCURATE ANSWERS✔✔ A mutation that
introduces a stop codon into a gene that encodes part of the LFA-1
molecule (leading to a truncated protein).
,Toll-like receptors for bacterial PAMPs are found on/in the -
ACCURATE ANSWERS✔✔ cell membrane
There are a few different proteins that act as inhibitors of NF-kB. There
is a very rare genetic disease in which one of these proteins, IkBα, is
mutated. The mutation substantially alters the stability of the IkBα
protein. In patients with this disease, IkBα protein expression does not
change in response to stimuli that cause IkBα degradation in healthy
individuals. Consider the biological role of NF-kB inhibitors. What are
the most likely symptoms of this genetic defect? - ACCURATE
ANSWERS✔✔ Immunodeficiency with a susceptibility to bacterial
infections.
The complement pathway initiated by host proteins that bind to
microbial sugars is called the ____________ pathway. - ACCURATE
ANSWERS✔✔ lectin pathway
ssRNA (single-stranded RNA) and dsDNA (double-stranded DNA) are
present in mammalian cells. Why don't our plasmacytoid dendritic cells
activate an innate immune response against these self nucleic acids that
are necessary for normal cellular function? - ACCURATE
ANSWERS✔✔ The TLRs that recognize ssRNA and dsDNA are
sequestered in endosomes.
How can the antiviral state be propagated in the absence of immune
cells? - ACCURATE ANSWERS✔✔ Type I IFNs are produced by
, infected epithelial cells; this induces anti-viral biochemical changes in
the same cell and adjacent cells.
A child presents with recurrent bacterial infections. Of the genetic
defects described below, what is the most likely cause of her disease? -
ACCURATE ANSWERS✔✔ A mutation in the C3 gene that renders the
C3 protein nonfunctional.
____________ is the process by which something that is not otherwise
recognized as a pathogen is coated with proteins that make it more
recognizable to the immune system. - ACCURATE ANSWERS✔✔
Opsonization
The majority of the symptoms of tetanus infection are caused by the
tetanus toxins, chiefly tetanospasmin. Tetanospasmin is one of the
deadliest toxins known; even very small doses (nanograms) can be
lethal. It targets the nerves, causing severe muscle spasms. The tetanus
vaccine consists of inactivated tetanus toxin; the vaccine is highly
effective for preventing tetanus. Inoculation with the tetanus vaccine
leads to the production of protective antibodies. How do these antibodies
prevent tetanus? - ACCURATE ANSWERS✔✔ Neutralization
Streptococcus pneumoniae is an extracellular bacterium that is a leading
cause of bacterial pneumonia and meningitis, particularly in children and
the elderly. Fortunately, most cases of S. pneumoniae can be prevented
with a vaccine that contains components of the bacterial capsule. The