An increase of three marks in Biology after revaluation changed the CBSE Class 12 exam result for Aditya Mishra of Bokaro. The revised score took his total to 498 out of 500 in his five best subjects, making him a joint national leader in the Science stream.When the CBSE results were declared on May 13, Aditya had scored 99.20 percent overall. He received 96 marks in Biology, but his teachers felt that the score was lower than expected. At that time, Aditya was focused on NEET exam preparation and did not pay attention to the result.“My parents and teachers submitted the document for reevaluation. I received three additional marks, bringing my biology score to 99,” he said on Tuesday.A student of DPS Bokaro, Aditya scored 100 marks each in English Core, Chemistry and Painting, with 99 marks in Physics and Biology.School principal AS Gangwar said the institution was proud of its achievement. He described Aditya as a sincere and consistent student who had always shown dedication towards academics.“We are very happy that one of our meritorious students, Aditya Mishra, has emerged as the national topper in the Science stream of the CBSE Class 12 examination after the revaluation,” said Gangwar.He added that Biology had always been Aditya’s favorite subject and that the school thought the paper deserved a revision after seeing the marks initially awarded.According to a teacher, Aditya shared the first position in the Science stream with Sonakshi Goyal from Kanpur.The son of Prajesh Chandra Mishra, managing director (finance) of SAIL Refractory Unit, and homemaker Sushmita Mishra, Aditya is now focused on his medical career. He also appeared in the NEET-UG re-exam held on Sunday.“I had also appeared for the NEET exam in May and the papers were good. But it was cancelled. I appeared for the re-examination and I am waiting for positive results,” he said.Aditya said he studied for five to six hours every day and used his mobile phone and laptop while preparing for the entrance test. In the future, he wants to join the medical profession.“I want to pursue my career in the medical field. I want to serve humanity as a doctor,” he said. His father credited the school and the teachers for playing a key role in his son’s success.