Maharashtra Board Class 12 Biology Past Paper 2024 PDF

# Biology (56) ## General Instructions: - The question paper is divided into four sections. - Evaluation will be done for the first attempt only. ### Section A: 1. **Q. No. 1:** Contains Ten multiple choice type of questions carrying one mark each. 2. **Q. No. 2:** Contains Eight very short answer...

# Biology (56) ## General Instructions: - The question paper is divided into four sections. - Evaluation will be done for the first attempt only. ### Section A: 1. **Q. No. 1:** Contains Ten multiple choice type of questions carrying one mark each. 2. **Q. No. 2:** Contains Eight very short answer type of questions carrying one mark each. ### Section B: - **Q. No. 3 to 14:** Are short answer type of questions carrying two marks each. - Attempt any Eight. ### Section C: - **Q. No. 15 to 26:** Are short answer type of questions carrying three marks each. - Attempt any Eight. ### Section D: - **Q. No. 27 to 31:** Are long answer type of questions carrying four marks each. - Attempt any Three. ### General Information: - Begin the answer of each section on a new page. # Section A ## Q. 1 Select the correct alternatives and write the answers: **(10)** ### (i) Identify the growth hormone in plants which causes inhibitory effect. **(a) Cytokinins** **(b) Abscissic acid** **(c) Gibberellin** **(d) Ethylene** ### (ii) Which one of the following is not a part of lac operon? **(a) Promoter** **(b) Regulator** **(c) Inducer** **(d) Operator** ### (iii) In absence of fertilization, corpus luteum degenerates into **(a) tunica albugenia** **(b) membrana granulosa** **(c) zona pellucida** **(d) corpus albicans** ### (iv) Which of the following divides nasal cavity? **(a) Hyaline cartilage** **(b) Mesethmoid cartilage** **(c) Ligamentum arteriosum** **(d) Laryngopharynx** ### (v) Which of the following is caused by unsterilized needle? **(a) Elephantiasis** **(b) AIDS** **(c) Malaria** **(d) Dengue** ### (vi) Recognition sequence of restriction enzymes are generally _nucleotides_ long. **(a) 2 to 4** **(b) 4 to 8** **(c) 8 to 10** **(d) 14 to 18** ### (vii) Which of the following types require pollinator but result is genetically similar to autogamy? **(a) Geitonogamy** **(b) Xenogamy** **(c) Apogamy** **(d) Cleistogamy** ### (viii) Which one of the following does not evolve further? **(a) Climax community** **(b) Primary Succession** **(c) Pioneer Species** **(d) Seral Community** ### (ix) Identify the appropriate term for the number of births under ideal conditions: **(a) Absolute mortality** **(b) Realized natality** **(c) Realized mortality** **(d) Absolute natality** ### (x) Observe the graph and select correct option: **A graph with a vertical axis representing Species Richness and a horizontal axis representing Area.** - **Line 'A'** represents S-CA² - **Line 'B'** represents log C = log A + Z log S - **Line A** represents S = CAZ - **Line B** represents log S = log Z + C log A # Section B ## Q. 2 Answer the following questions: **(8)** ### (i) What are vestigial organs? ### (ii) Expand the term ZIFT. ### (iii) Give the name of endocrine gland which is prominent at birth but gets gradually atrophied in adult stage. ### (iv) What is the full form of IAA? ### (v) Give the name of microbial source of antibiotic chloromycetin. ### (vi) Which cells of islets of Langerhans produce a hormone insulin? *https://www.maharashtrastudy.com* ### (vii) How many meiotic divisions are required for the formation of 300 seeds in angiosperm? ### (viii) Explain the term Emigration. ## Q. 3 What are the reasons for the success of Mendel? **(16)** ## Q. 4 Arrange the following steps of DNA fingerprinting in correct sequence: **(a) Gel electrophoresis** **(b) Isolation of DNA** **(c) Southern blotting** **(d) Restriction digestion** ## Q. 5 Distinguish between human sperm and ovum. ## Q. 6 Enlist the uses of gene therapy. ## Q. 7 Define the following terms: ### (a) Gene flow ### (b) Chromosomal aberrations ## Q. 8 What are the significances of double fertilization? ## Q. 9 Identify and define 'A' and 'B' in relation to uptake of water by the root: **An image of a root with two parts labeled: 'A' and 'B'.** ## Q. 10 Describe mutualism. ## Q. 11 Explain factors affecting water absorption. ## Q. 12 What is differentiation and redifferentiation? ## Q. 13 Select and rewrite appropriate disorder of respiratory system with the given symptoms: **[ sinusitis, emphysema, silicosis and asbestosis, laryngitis ]** **(a) Breakdown of alveoli, shortness of breath.** **(b) Inflammation of the sinuses, mucous discharge.** **(c) Inflammation of larynx, vocal cord, sore throat, hoarseness of voice, mucous build up and cough.** **(d) Inflammation of fibrosis, lung damage.** ## Q. 14 Explain the steps involved in preliminary treatment of sewage. # Section C ## Q. 15 Give the different steps involved in the formation of m-RNA from hn-RNA. **(24)** ## Q. 16 What is reproductive isolation? Describe any two types each of pre-mating and post-mating isolating mechanism. ## Q. 17 Explain unique features of acquired immunity. ## Q. 18 Name and describe hormones secreted by ovaries. ## Q. 19 Explain different steps involved in PCR technique. ## Q. 20 **An image of three cells labeled: 'A', 'B' and 'C'.** Identify A, B, and C from the above diagrams and give their functions. ## Q. 21 What are the limitations of root pressure theory? ## Q. 22 Explain green house effect with reference to gases responsible for it and their sources. ## Q. 23 Describe physiological effects and applications of ethylene. ## Q. 24 Give the name and type of I, IV and VII cranial nerves. ## Q. 25 Describe pyramid of energy with the help of diagram. ## Q. 26 What is lac? Enlist economic importance of Lac. # Section D ## Q. 27 Describe histological structure of Testis with well labelled diagram. **(12)** ## Q. 28 What are chromosomal disorders? Describe Turner's syndrome and Klinefelter's syndrome. ## Q. 29 Describe nervous system in planaria with well labelled diagram. ## Q. 30 Explain following terms: ### (a) Grafting ### (b) Apomixis ### (c) Polyembryony ### (d) Parthenocarpy ## Q. 31 Interpret the given diagrams A and B. Enlist the changes occurring during inspiration and expiration. **Two diagrams of a human body: one labeled 'A' and another labeled 'B', showing the expansion and contraction of the lungs.**