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Human Health and Disease — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease1 Mark
MCQ
For question two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion : Inflammatory response is produced in the body after some infections.
Reason: This is one type of defence mechanism.
  • ✓
    Both assertion and reason are true and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true but reason is not the correct explanation of assertion.
  • C
    Assertion is true but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: A.
Both assertion and reason are true and reason is the correct explanation of assertion.
Infection or tissue injury often results in redness and swelling, along with pain and production of heat that may result in fever. Such manifestation is localized and, is known as inflammatory response. This response occurs due to release of chemical signals, alarm signals, notably histamine and prostaglandins,by the damaged mast cells. There is a leakage of vascular fluid, which contains serum proteins with antibacterial activity. Further, there is an influx of phagocytic cells into the affected area. These responses inhibit and destroy the invading microorganisms. Thus, inflammatory response is said to be a defence mechanism.

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