Elite Tuition Centre Class 12th Biology Test PDF

## ELITE TUTION CENTRE ### Class 12th BIOLOGY TEST **50 marks** ### Q.1 Match column I with column II and select the correct option from the given codes. | Column I | Column II | |---|---| | A. Dihybrid test cross | (i) 9:3:3:1| | B. Law of segregation | (ii) Dihybrid cross | | C. Law of assortmen...

## ELITE TUTION CENTRE ### Class 12th BIOLOGY TEST **50 marks** ### Q.1 Match column I with column II and select the correct option from the given codes. | Column I | Column II | |---|---| | A. Dihybrid test cross | (i) 9:3:3:1| | B. Law of segregation | (ii) Dihybrid cross | | C. Law of assortment independent | (iii) 1:1:1:1 independent | | D. ABO blood group | (iv) Purity of gametes in man | | | (v) Multiple allelism | (1) A-(iii), B-(iv), C-(ii), D-(v) (2) A-(i), B-(iv), C-(ii), D-(v) (3) A-(iii), B-(ii), C-(iv), D-(v) (4) A-(ii), B-(v), C-(iii), D-(i) ### Q.2 All of the following contributed to Mendel's success except (1) Mendel's selection of pea plant for experiments (2) Application of mathematical knowledge (3) Working on small sampling size at a time (4) Taking one character at a time. ### Q.3 Match column I with column II and select the correct option from the given codes. | Column I | Column II | |---|---| | A. Multiple alleles | (i) Phenylketonuria in humans | | B. Polygenes | (ii) Blood group in humans | | C. Pleiotropy | (iii) Skin colour in humans | (1) A-(ii), B-(i), C-(iii) (2) A-(ii), B(iii), C-(i) (3) A-(iii), B-(ii), C-(i) (4) A-(i), B-(iii), C-(ii) ### Q.4 Mendel crossed TT x tt. Which of the following is incorrect? (1) F1 progeny were all tall. (2) F2 progeny were all parental type. (3) In F1 progeny, blending has not occurred. (4) 50% intermediate phenotypes were observed in F2 progeny. ### Q.5 Which of the following is incorrect regarding ZW-ZZ type of sex determination? (1) It occurs in birds and some reptiles. (2) Females are homogametic and males are heterogametic. (3) 1:1 sex ratio is produced in the offsprings. (4) All of these ### Q.6 Match column I with column II and select the correct option from the given codes. | Column I | Column II | |---|---| | A. Autosomal recessive traits | (i) Down's Syndrome | | B. Sex-linked recessive trait | (ii) Sickle cell anemia | | C. Metabolic error linked to autosomal recessive trait | (iii) Haemophilia | | D. Additional 21st Chromosome | (iv) Phenylketonuria | ### Q.7 Incorrect about Mendelian disorders (1) Can be dominant or recessive (2) These can be traced with pedigree analysis (3) These are present on autosomes only (4) Mutation occurs in single gene usually. ### Q.8 XO type of sex determination can be found in (1) Birds (2) Grasshoppers (3) Monkeys (4) Drosophila ### Q.9 Dihybrid cross proves the law of: - (1) Segregation (2) Purity of gametes (3) Dominance (4) Independent assortment ### Q.10 A cross between AaBB X aa BB yields a genotypic ratio of: - 1) 1 AaBB: 1 aaBB 2) 1 AaBB: 3 aaBB 3) 3 AaBB: 1 aa BB 4) All AaBb ### Q.11 Select the incorrect statement regarding pedigree analysis. (1) Solid symbols show unaffected individuals. (2) Proband is the person from which case history starts. (3) It is useful for genetic counsellors. (4) It is an analysis of traits in several generations of a family. ### Q.12 Select the incorrect statement (1) Male child may become haemophilic if his mother is a carrier for haemophilia. (2) Sickle cell anaemia is a classical example of chromosomal mutation. (3) Gynaecomastia develops in Klinefelter's syndrome. (4) Trisomy of chromosome number 21 results in Down's syndrome. ### Q.13 How many types & in what ratio the gametes are produced by a dihybrid heterozygous: - 1) 4 types in the ratio of 9:3:3:1 2) 2 types in the ratio of 3:1 3) 3 types in the ratio of 1:2:1 4) 4 types in the ratio of 1:1:1:1 ### Q.14 Who rediscovered the results of Mendel's experiments: - 1) DeVries, Tschemark, Correns 2) DeVries, Tschemark, Morgan 3) Tschemark, Morgan, Correns 4) Tschemark, Bateson, Punnet ### Q.15 If 120 Plants are produced on crossing pure red and pure white flowered pea plants, then the ratio of offsprings will be: 1) 90 Red: 30 White 2) 30 Red: 90 White 3) 60 Red: 60 White 4) All red ### Q.16 When an F 1 individual is crossed with its either of the two parents. Then it is known as: - 1) Test cross 2) Back cross 3) Reciprocal cross 4) Monohybrid cross ### Q.17 According to Mendel, "factors" or "genes" 1) are the units of inheritance 2) contain information that is required to express a particular trait 3) Both 1 and 2 4) None of the above ### Q.18 In case of incomplete dominance, F2 generation has 1) Genotypic ratio equal to phenotypic ratio 2) Genotypic ratio is 3:1 3) Phenotypic ratio is 3:1 4) None ### Q.19 A man of A blood group marries a woman of AB blood group. which type of progeny would indicate that man is heterozygous A: - 1) AB 2) A 3) Ο 4) B ### Q.20 A polygenic inheritance in human beings is 1) skin colour 2) sickle cell anaemia 3) colour blindness 4) phenylketonuria ## Descriptive ### Q.1 In snapdragon, a cross between true-breeding red flowered (RR) plants and true-breeding white flowered (rr) plants showed a progeny of plants with all pink flowers. (i) The appearance of pink flowers is not known as blending. Why? (ii) What is this phenomenon known as? ### Q.2 (i) Explain the phenomenon of multiple allelism and codominance taking ABO blood groups as an example. (iii) What is the phenotype of the following? a) I^i b) ii ### Q.3 Explain the mechanism of sex-determination in birds. How does it differ from that of human beings.? ### Q.4 What is pedigree analysis? Explain how such an analysis can be useful. ### Q.5 During a medical investigation, an infant was found to possess an extra chromosome 21. Describe the symptoms the child is likely to develop later in life. ### Q.6 (i) Explain a monohybrid cross taking seed coat colour as a trait in Pisum sativum. Work out the cross upto F2 -generation. (ii) State the laws of inheritance that can be derived from such a cross. (iii) How is the phenotypic ratio of F2-generation different in a dihybrid cross? ### Q.7 cross was carried out between two pea plants homozygous dominant for yellow and round seeds with homozygous recessive for the same trait. The F2 progeny of such a cross showed phenotypic ratio of 9:3:3: 1. (i) State the different laws of Mendel that could be derived from such a cross. (ii) Write the possible genotypes for the progeny for such a cross having a. yellow and wrinkled seeds b. green and round seeds ### Q.8 How is sex determined in humans? ### Q.9 Study the given pedigree chart showing inheritance of sickle cell anaemia and answer the questions that follows [The diagram shows a pedigree chart with 5 individuals. Each individual is represented by a square (male) or circle (female). The individuals are labelled 1, 2, 3, 4 and 5. Individual 1 marries individual 2 and they have children 3 and 4. Individual 3 marries individual 5 and they have a child labelled 5.] (i) Is the trait recessive or dominant? (ii) Is the trait sex-linked or autosomal? (iii) Give the genotype of the parents.