Correct answer: B). The phagocytotic barrier, which is a part of innate immunity
The scenario represents the phagocytosis, which is a type of endocytosis by which the cell engulfs microbial pathogens. The main cells of the immune system that are involved in phagocytosis include macrophages, neutrophils, and dendric cells.
It is a mechanism which is used by the immune system to kill and processing of antigen that play an important role in innate immune response.
Hence, the correct answer would be option B.
The correct answer is b.
The child is reaching for a toy which is not visible to him (hidden under a cloth), therefore, the child has a mental representation of the object in his/her mind. This action means that the child acknowledges that the objects continue to exist even when he/she can not hear or see them. This thought process is called object permanence and it is an ability acquired between the 4th and 7th month of a child's development.
The correct answers is:
is formed when fuel is burned at high temperatures
<em>Nitrogen dioxide is another toxic gas that forms when fuels are burned at high temperatures.</em>
is the most abundant gas in the atmosphere
<em>The most abundant gas is nitrogen. Over 78 percent of the air we breathe is nitrogen (N)</em>
can cause acid rain
<em>Both nitrogen dioxide and sulfur dioxide can cause acid rain. The damage done by acid rain is devastating to the plants and animals in an ecosystem.</em>
is a major pollutant in the air
<em>AQI measures five major pollutants, including carbon monoxide, nitrogen dioxide (NO2), and sulfur dioxide (SO2).</em>
Wrong answers:
is a waste product of photosynthesis
<em>The waste product of photosynthesis is oxygen.</em>