Video Transcript
Which of the following is not a
benefit of the blood being able to form clots? (A) It helps limit the spread of
pathogens. (B) It prevents excessive bleeding
from a wound. (C) It can restrict blood flow to
nonessential organs. Or (D) it forms a protective
barrier to prevent a wound becoming infected.
In order to answer this question,
let’s first think about what are benefits of the blood being able to form clots.
The blood clotting process begins
in response to damage to the epithelial lining of a blood vessel. This happens because the clot helps
to plug the damaged portion of the vessel to prevent too much blood from
escaping. So one benefit of a blood clot is
that it reduces bleeding after an injury. Additionally, by blocking this
potential opening from the outside into the inside of the body, the clot helps
prevent outside pathogens from entering through the damaged area. So it helps reduce the spread of
pathogens into the body and therefore also reduces the likelihood of the wound
becoming infected.
One problem that a blood clot can
cause is that it can potentially restrict or even block blood flow through a vessel,
in which case the tissues or organs that are normally supplied blood by that vessel
will not receive the normal amount of blood flow and as a result may be starved of
oxygen or nutrients that are carried by the blood.
Now that we have some idea of the
effects of clots on the body, let’s look back at our question and answer
choices. We are asked which of the answer
choices is not a benefit of the blood being able to form clots. We know that clots do help limit
the spread of pathogens. We also know that clots do prevent
excessive bleeding from a wound and that they do help reduce the likelihood of
infection of the wound. Blood clots can restrict blood flow
in some cases, but that’s not a benefit. Instead, we would consider this a
problem that clots can cause.
So the answer choice that is not a
benefit of the blood being able to form clots is (C). It can restrict blood flow to
nonessential organs.
