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Human Health and Disease — BIOLOGY STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Health and Disease1 Mark
Question
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.
  1. Both assertion and reason are true, and reason is the correct explanation of assertion.
  2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
  3. Assertion is true, but reason is false.
  4. Both assertion and reason are false.
Assertion : Dendritic cells originate in the bone marrow.
Reason: Dendritic cells are found in neuron.
✓

Answer

  1. Assertion is true, but reason is false.

Explanation:

Dendritic cells are immune cells and form part of the immune system. They are present in those tissues which are in contact with the environment; in the skin (where they are often called Langerhans cells) and the lining of nose, lungs, stomach and intestines. They have long spiky arms, called dendrites, hence the name. (Neurons also have dendrites, but dendritic cells have nothing to do with neurons).

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