* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Biology Question Paper and Marking Scheme
Gene therapy of the human retina wikipedia , lookup
Site-specific recombinase technology wikipedia , lookup
X-inactivation wikipedia , lookup
Gene therapy wikipedia , lookup
Molecular cloning wikipedia , lookup
Genomic library wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Epigenetics of neurodegenerative diseases wikipedia , lookup
Genetic engineering wikipedia , lookup
Public health genomics wikipedia , lookup
Therapeutic gene modulation wikipedia , lookup
Cell-free fetal DNA wikipedia , lookup
Neuronal ceroid lipofuscinosis wikipedia , lookup
History of genetic engineering wikipedia , lookup
Expanded genetic code wikipedia , lookup
Helitron (biology) wikipedia , lookup
Vectors in gene therapy wikipedia , lookup
Microevolution wikipedia , lookup
Point mutation wikipedia , lookup
Genome (book) wikipedia , lookup
Designer baby wikipedia , lookup
1st Pre-board Exam (2014-15) Class-XII Subject-biology Time:3 Hrs.] [M.M.:70 General instructions1. All questions are compulsory. 2. Attempt all questions serially only. 3. Marks are assigned against each question. SECTION-A Q.1 What forms the backbone of a polynucleotide strand of a nucleic acid? 1 Q.2 Write the scientific name of the aquatic weed known as terror of Bengal. 1 Q.3 In insecticidal protein called Bt toxin has been used these days. What do the letter Bt stand for? 1 Q.4 When do the oogenesis initiate in human females? 1 Q.5 Name the vector used for introducing the nematode specific gene in tobacco plant? 1 SECTION-B Q.6 How do the tRNA molecules appear in(a) Two diamentional view. (b) Three diamentional view. 2 Q.7 Write the names of the following. (a) Semi dwarf, high yielding and disease resistant variety of wheat. (b) One interspecific hybrid mammal. 2 Q.8 Mention the brain capacities of the following (a) Homo habilis (b) Neanderthal man 2 Q.9 Write the names of the organic materials, the exine and intine of an angiosperm pollen grain are made up of? 2 Q.10 Expand the following. (I) BAC (II) YAC 2 SECTION-C Q.11 (a) Write the name of the two species of filarial worms causing filariasis . 3 (b) How does the disease spread? Q.12 A haemophilic man marries a normal homozygous women. What is the probability that their daughter will be haemophilic. Explain with cross & give reason. 3 Q.13 Fill in the spaces a,b,c in the table showing certain events and their sites in human (male/female) reproductive system. 3 S.N. Event Site 1. Release of 1st polar body a__________ 2. Spermeiogenesis b__________ 3. Fertilisation c__________ Q.14 (a) Name the phase all organisms have to pass through before they can reproduce sexually. 3 (b) Name the vegetative propagules of. (I) Bryophyllum (II) Agave. Q.15 Many patients reject the transplanted organ as it is not histocompatible with their tissues. 3 (A) Which drug is used to prevent the rejection of the organ? (B) From which organism is it derives? (C) How it works? Q.16 There are sixty four codons in the genetic code dictionary. 3 (A) How many of them code for amino acids? (B) How many amino acids are coded? (C) What general term is given to the codons which do not code for amino acids? Q.17 Identify the pollutants responsible for causing the following effects. 3 (A) Biomagnification (B) Eutrophication (C) Snow blindness cataract. Q.18 (a) what would be ploidy level of Endosperm if a tetraploid male plant is crossed with diploid female plant? 3 (b) How many Meiotic and mitotic divisions would a microspore mother cell undergo to form pollen-grain? (c) How many Meiotic and mitotic divisions would a megaspore mother cell undergo to form an embryo sac? Q.19 Label ‘a’ ‘b’ ’c’ stages in central dogma & briefly describe. ‘a’ 3 DNA –‘B’------→mRNA ---‘c’------→ Protein Q.20 Name the type of interaction in each of the following - 3 (A) Sucker fish attached to shark (B) Cockoo lays eggs in crow’s nest (C) Sea anemone found on shell of hermit crab. Q.21 (a) Expand MOET. 3 (b) Following are the steps in MOET programme for Herd improvement; in which cows have been administered hormones like FSH. Arrange the steps in correct sequence .These are the steps. (A)Transferred to a Surrogate mother (B)It is either mated with an elite bull or artificially inseminated. (C)Fertilized eggs at 32 cell stage are recovered non surgically. (D) It produces 6-8 eggs instead of one egg which they nor yield per cycle. Q.22 Draw a simplified model of Phosphorus cycle in a teressrial ecosystem. 3 OR Draw a simplified model of Carbon cycle in Biosphere. SECTION-D Q.23 A person on your group Housing Society has recently been diagnosed with AIDS. Many members of the Society as they are scared of the spread of the disease. 4 (A) Give full scientific name of Causative agent. (B) W rite the symptoms of the disease. (C) Mention the routes of transmission of the disease. (D) Write your view on the situation. SECTION-E Q.24 What are the five features required to facilitate cloning into a vector. Explain each with suitable diagram with suitable example for each briefly explain the application of Biotechnology in medicine. 5 Q.25 (A) List the three different allelic forms of gene I in humans. Explain the different phenotypic expressions controlled by these three forms. (B) A women with blood group A marries with blood group O. Discuss the possibilities of the inheritance of the blood groups in the following starting with “yes” or “no” for each. (Make cross foe each) (I) They produce children with blood group “A” only. (II) They produce children some with “O” blood group and some with “A” Blood group. OR Name the scientists who proved experimentally that (I)DNA is genetic material. (II) DNA replication is semi conservative with the help of diagram describe the experiments. Q.26 (a) Describe the particular type of agriculture which is also responsible for deforestation.5 (b) Study the population growth curves in the graph given below and answer the questions which follow (I)Identify the growth curves ‘a’ and ‘b’ explain. (II) Which one of them is considered more realistic one and why? (Iii) If dN/dt=rN[K-N/K] is the equation of one the growth curves , what does ‘k’ stands for . (IV) What is symbolized by N? OR (a) Explain with the diagram and specific example for each that how hydrarch succession proceeds from hydric to mesic condition to form a stable community. (b) Why is secondary succession faster than primary succession. Marking scheme First pre-board examination 2014-15 Class XII Subject : biology SECTION-A Q.1 sugar phosphate 1/2+1/2 Q.2 Eichhornia crassipes 1 Q.3 Bacillus thuringiensis 1 Q.4 In foetal ovary 1 Q.5 Argobacterium tumifaeeins 1 SECTION-B Q,6 (a) Clover leaf like form 1 (b) ‘L’ shaped form 1 Q.7 (a) Kalyan ,sona,sonalika. 1/2*2 (b) Mule – female horse + male donkey Q.8 (a) 600-800 c.c 1 (b) 1400 c.c 1 Q.9 Exine sporopollenin 1+1 Intine –cellulose Q.10 (i)Bacterial artificial chromosome 1 (ii) Yeast artificial chromosome 1 1/2+1/2 SECTION-C Q.11 (a) Wuchereria Bancrafti 1 +1 W.Malyi (b) Bite of mosquito : vector 1 Q.12 Female XX * Xh Y xx Xh y x xxh xy y xxh xy xxh Normal xy Female Normal male (carrier) --All dauters are normal but carrier 1/2 -- x linked recessive gene diseases 1/2+ 3 -- pure, so male is always homozygous --to be expressed in female it should be homozygous I.e, xhxh Q.13 (a) ovary 1*3 (b) seminiferous tubules ( c ) ampullary isthmic junction of fallopian tube Q.14 (a) juvenile phase 1 (b) (i) buds on leaf 1 (ii) bulbils 1 Q.15 (a) Cyclosporins 1 (b) Trichoderma polysporum 1 (c ) Immuno suppresants 1 Q.16 (a) 61 1 (b)20 1 (c )Termination Nonscence condom 1 Q.17 (a) Excessive pesticides 1*3 (b) use of nitrogenous fertilizers /wastes washed to water bodies (c) U.V.B radiation which affect cornea Q.18 (a) Tetraploid – explaination for each (b) One meiosis 1 1 (c ) One meiosis and three mitosis division 1 Q.19 (a) Replication 1*3 (b) Transcription (c) Translation Q.20 (a)commensalism – brief description 1/2+1/2 =1 *3 (b)Blood Parasitism - brief description (c) mutualism Q.21 (a) Multiple ovulation Embryo transfer technology 1 (b) D.C.B.A 1/2*4 Q.22 Refer N.C.E.R.T Page no.255 fig 14.7 1/2 *6 Or Refer N.C.E.R.T Page no.253 fig 14.6 SECTION –D Q.23 -Human Immuno Deficiency Virus -Symtoms of AIDS 1 1 -Causes eg. Blood transfusion, used syringe ,unprotected sex, shaving blade any other. 1 -it is not spread by mere contact like eating ,hugging ,they should treat sympathetically and rehabitilate them . 1 SECTION- E Q.24 1. Origin of replication . 1*5 2. selectable marker 3. cloning sites 4. insertional inactivation 5. Vectors for cloning genes in plants and animals Or (i) (ii) (iii) Genetically Engineered Insulin + diagram Gene Therepy Molecular diagnosis 1+1 1+1/2 1+1/2 Brief explanation of each. Q.25 (a) IA ,IB , i; 1/2 N.C.E.R.T Page no. 77 table 5.2 1+1/2 (b) (i) No – show cross if woman is heterozygous 1/2 *3 Reason and explanation (ii) Yes – cross 1/2*3 Reason and explanation OR (i) Alferd Hershey and Martha Chase – 1/2 experiment and diagram refer N.C.E.R.T (ii) Messelson and stahl 1/2 N.C.E.R.T Page 105 fig. 6.7 Diagram 1 Explaination 1 Q.26 (a) Jhum cultivation or slash and burn agriculture Description 1/2+1/2 (b) (i) (a) exponential - explaination 1+1 (1/2*4) (b) logistic - explaination (ii) Ligistic – reason (ii) (iii) 1/2+1/2 Carrying capacity Population density Or (a) N.C.E.R.T Page 251 diagram 2 Diagram page 252 explaination 2 Reason 1 1/2 1/2 1+1