Answer: Option D
Explanation:
Once the pathogen enters the body, it starts dividing and after a certain period of time the patients experience some sign and symptoms of illness.
The prodromal period occurs just after the incubation period. In this phase the pathogen keeps on dividing and the host begins to experience general symptoms and signs of illness.
This is a result of the activation of immune system of the body which results in the swelling, pain, soreness.
Red blood cells will swell and burst. The
reason behind this is that red blood cells are okay when they are in
the plasma (the watery part of the blood) because the solutes in plasma
are so well balanced that plasma is rendered isotonic. An isotonic
solution is a type of solution that has the same salt concentration as
its surrounding environment and thus the substances around it e.g. cells
neither gain nor lose water. In the blood plasma, the red blood cells
neither lose nor gain water and so they remain intact.<span>However distilled
water is hypotonic (has less or no solutes) and therefore osmosis will
take place when red blood cell which have a higher solute concentration
are placed in it. Water molecules will leave the distilled water and
pass into the red blood cells through the semi-permeable membrane of the
cells in an attempt to equalize the difference in osmotic pressure on
either side of the membrane. In so doing, water will accumulate in the
cell which will then swell to capacity and ultimately burst.</span>
Because of the evaporated particles that mix with the air molecules and then our sense of smell tells us what's cooking.
