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Cells that target and kill body cells infected by viruses are
a. macrophages.
b. natural killer cells.
c. monocytes.
d. neutrophils.
Introduction:
Innate is the non-specific type of defense of body which develops quickly. It provides general response regardless of pathogen type and exposure numbers. It nonspecifically kills the pathogen that invades the body. Phagocytic cells are the part of the innate immunity that circulates in the body and attack the pathogens.
Answer to Problem 1U
Correct answer:
Natural killer cells are the cells that targets and kill body cells infected by viruses. Therefore, option b. is correct.
Explanation of Solution
Reason for the correct statement:
The small populations of lymphocyte that act in distinct manner than the other lymphocytes that participates in the adaptive defense mechanism are known as natural killer cells. They do not kill pathogen by phagocytosis instead they kill the cells of the body that infected with virus through apoptosis (programmed cell death).
Option b. is given as “natural killer cells”.
As, “the cells that target and kill the virus infected body cell with the process of programmed cell death (apoptosis) are natural killer cells, is the right answer.
Hence, option b. is correct.
Reason for the incorrect statements:
Option a. is given as “macrophages”.
Macrophages are irregular large shaped cells that kill the pathogen by phagocytosis. So, it is a wrong answer.
Option c. is given as “monocytes”.
Monocytes are undifferentiated macrophages that mature into “active phagocytic macrophage” at the site of infection. So, it is a wrong answer.
Option d. is given as “neutrophils”
These are the first cells that appear on the site of the infection and perform phagocytosis with even high range of reactive radicals of oxygen. So, it is a wrong answer.
Hence, option a., c., and d. are incorrect.
Natural killer cells are the cells that provide immunity against viruses and cancer cells by inducing programmed cell death of the infected cell.
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Chapter 51 Solutions
BIOLOGY VOL. II
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