Trending ▼   ResFinder  

ISC Class XII Board Exam 2020 : Biotechnology Paper 2 (Practical)

3 pages, 16 questions, 0 questions with responses, 0 total responses,    0    0
ISC 12th
Indian School Certificate Examination (ISC), New Delhi
+Fave Message
 Home > isc >

Formatting page ...

BIOTECHNOLOGY PAPER 2 (PRACTICAL) (Maximum Marks: 30) (Time allowed: Three hours) (Candidates are allowed additional 15 minutes for only reading the paper. They must NOT start writing during this time.) ------------------------------------------------------------------------------------------------------------------------Answer all questions. The intended marks for questions or parts of questions are given in brackets [ ]. ------------------------------------------------------------------------------------------------------------------------Question 1 (a) Take a 2'' piece of a ripe banana in a 100 ml beaker. Mash it properly. To this, add 30 ml of extraction fluid (labelled EF) provided to you. Incubate the beaker at 60oC for 15 minutes. Stir the contents of the beaker gently with a glass rod and filter the content. Allow the filtrate to cool. Take 5 ml of filtrate in a test tube and label the test tube as D. Gently add 5 ml of ice-cold 90% ethanol to test tube D. Allow the test tube to stand for 10 minutes. Show the test tube to the Visiting Examiner. Answer the following questions: (b) (i) Name the substance obtained in the test tube after the completion of the experiment. [1] (ii) State the method that will be used to extract the isolated substance from the test tube. [1] (iii) Name the two contaminants present in test tube D, along with the isolated substance. [1] You are provided with vegetable oil (coconut oil), common salt (NaCl) and 20% sodium hydroxide (NaOH) solution. Take 25 ml of vegetable oil in a measuring cylinder and pour it into a 250 ml glass beaker. Measure 30 ml of 20% NaOH solution in another measuring cylinder. Pour it into the beaker containing vegetable oil. Stir the mixture using a glass rod. Place the beaker on a wire gauze placed over a tripod stand. Heat the beaker on a Bunsen burner till the mixture turns into whitish paste. ---------------------------------------------------------------------------------------------------------------------------This paper consists of 3 printed pages and 1 blank page. 1220-878B Turn over Copyright reserved.

Formatting page ...

Formatting page ...


  Print intermediate debugging step

Show debugging info


Tags : ISC Board, Council for the Indian School Certificate Examinations, ISC 2021 - 2022 Examination, 2022, 2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, ISC Solved Specimen Question Papers 2021 - 2022, ISC Solved Mock Guess Exam Papers, ISC Board Model Paper with Answers, Detailed Solutions & Explanations, isc sample question bank, past / old / last year online test papers, syllabus, online coaching.  

© 2010 - 2022 ResPaper. Terms of ServiceContact Us Advertise with us


isc chat