Question Based on Paragraph - Physics

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For the past some time, Aarti had been observing some erratic body movement, unsteadiness and lack of coordination in the activities of her sister Radha, who also used to complain of severe headache occasionally. Aarti suggested to her parents to get a medical check-up of Radha. The doctor thoroughly examined Radha and diagnosed that she has a brain tumour.

(a) What, according to you, are the values displayed by Aarti?

(b) How can radioisotopes help a doctor to diagnose brain tumour?

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Solution

(a) Aarti has displayed awareness and care towards the health of her sister.

(b) During the intake of different elements and compounds, the biological organisms absorb them differently. Also, the exact distribution of the elements and their function in the various parts of organisms cannot be known clearly. For this, a radioisotope is made to enter the organism along with the elements and compounds, whose absorption, functioning and distribution to the brain has to be studied. The radioisotope acts as a tag of label for the element or compound under study. By detecting the radiation emitted by the isotope from the brain, the details regarding the absorption and function of the compounds by the organisms are found out. In this way, radioisotopes help a doctor to diagnose brain tumour.

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2013-2014 (March) All India Set 2

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