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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 : Cornea is considered as an immunologically privileged site
Reason: A transplanted cornea is rarely rejected.
  • ✓
    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.
Some transplanted tissues do not stimulate an immune response. For example, a transplanted cornea is rarely rejected because lymphocytes do not circulate into the anterior chamber of the eye, thats why this site is considered as immunologically privileged site.

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