2019 Biology (Theory) Past Paper PDF - OCR

Total No. of Printed Pages ––8 (2) HS/XI/Sc/Bio/19 (iv) Question numbers 6–10 are to be answered in one word or...

Total No. of Printed Pages ––8 (2) HS/XI/Sc/Bio/19 (iv) Question numbers 6–10 are to be answered in one word or one sentence each. 2019 (v) Question numbers 11–17 are to be answered in BIOLOGY approximately 20–30 words each. ( Theory ) (vi) Question numbers 18–26 are to be answered in approximately 30–50 words each. Full Marks : 70 Time : 3 hours (vii) Question number 27 is to be answered in approximately 70–100 words. General Instructions : (viii) Question numbers 28–30 are to be answered in approximately 80–120 words. (i) This question paper consists of 5 Sections A, B, C, D and E. Section A consist of A1 and A2. Section A1 consist of 5 questions of one marks each. Section A2 consists of 5 questions of one marks each. Section B consist of 7 questions of two marks each, Section C is of 9 questions of SECTION – A1 three marks each, Section D consist of 1 question of four mark and section E is of 3 questions of 5 marks each. Choose the correct answer : 1  5=5 1. Which of the following contains hydrolytic enzymes? (ii) All questions are compulsory. (a) Ribosome (iii) There is no overall choice. However, an internal choice has (b) Lysosome been provided in two questions of two marks, in two questions of three marks and in all the three questions of (c) Plastids five marks weightage. Attempt only one of the choices in (d) Mitochondria. such questions. HS/XI/Sc/Bio/19 HS/XI/Sc/Bio/19  (3) (4) 2. Synapsis occurs during SECTION – A2 (a) Leptotene (Very short answer) 1  5=5 (b) Zygotene (c) Pachytene 6. Define Plasmolysis. (d) Diplotene. 7. What are saprophytes? 3. Which of the following is a modified root ? (a) Potato 8. Which hormonal deficiency is responsible for diabetes mellitus? (b) Sweet potato (c) Ginger 9. Name any two types of nitrogenous base found in (d) Onion. nucleic acids. 4. The Non-Nucleated cell found in blood is 10. Give the scientific name of cockroach. (a) RBC (b) WBC (c) Thrombocytes SECTION – B (d) All the above. (Short answer – 1) 2  7 = 14 5. The hormone secreted by pineal gland is 11. Either, (a) Melanin Give the salient features of mosses. (b) Melatonin Or (c) Melanocytes Write down the characteristic features of dinoflagellates. (d) All the above. HS/XI/Sc/Bio/19 HS/XI/Sc/Bio/19  (5) (6) 12. What is inflorescence ? Define racemose inflorescence With the help of a suitable diagram explain the internal with examples. 1+ 1=2 structure of monocot stem. 1+ 2=3 13. Name any two micronutrients and mention atleast one 19. Describe briefly the four major groups of Protozoa. To deficiency symtom for each. 1+ 1=2 which group does the malarial parasite belong. 2 + 1 = 3 14. What is a peptide bond? How are they formed? 1 + 1 = 2 20. Give a labelled diagram of a plant cell. Explain the function of cell membrane. 2+ 1=3 15. Draw a well labelled diagram of a myelinated neuron. 2 21. Explain the electron transport system in the light 16. What is the role of HCl in digestion? 2 reaction of photosynthesis. 17. Either 22. How is a “pull” created during transpiration. Differentiate between open circulatory system and closed circulatory system. 2 23. Write three diagnostic characters of chordates. Or 24. Describe briefly any three factors affecting enzyme Differentiate between ammonotelic and ureotelic activity. excretion. 2 SECTION –– C 25. Draw a labelled diagram of a myofibril of skeletal muscle 3  9 = 27 showing different region. ( Short answer – II ) 18. Either 26. Either Explain different types of simple tissues found in Explain conduction of nerve impulse along a nerve plants. Give suitable diagrams. 2+ 1=3 fibre. Or HS/XI/Sc/Bio/19 HS/XI/Sc/Bio/19  (7) (8) Or SECTION – E Explain the transmission of nerve impulse across a ( Long answer type ) 5  3 = 15 synapse. 28. Either SECTION – D Explain the process of glycolysis. Or 27. Value based question 4  1=4 Write a note on C4 pathway. 29. Either Give an account of Calvin cycle. Or Mention the characteristics of phylum Arthropoda. 30. Either The above figure shows the effect of light on the rate of photosynthesis. Based on the graph, answer the Describe in detail the digestion of protein as they pass following questions. through the human digestive system. Or (a) At which region(s) (A, B or C) in the curve is light a limiting factor ? 1 Describe the process of urine formation in humans. (b) What could be the limiting factor(s) in region A ? 1  (c) What do C and D represent on the curve ? 2 HS/XI/Sc/Bio/19 HS/XI/Sc/Bio/19