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7., , 9, , Which one of the following traits of garden pea studied by, Mendel was a recessive feature ?, , (a) Round seed shape (b) Axial flower position, (c) Green seed colour (d) Green pod colour, , The genes controlling the seven pea characters studied by, Mendel are now known to be located on how many different, chromosomes ?, , (a) Four (b) Seven, , (c) Six (d) Five, , In a certain plant, red fruit (R) is dominant over yellow fruit, (r) and tallness (T) is dominant over shortness (t) .If a plant, with RRTt genotype is crossed with a plant rrtt genotype ,, what will be the percentage of tall plants with red fruits in the, , progeny ?, (a) 50% (b) 100%, (c) 75% (d) 25%, , Independent assortment of genes does not take place when, , (a) genes are located on homologous chromosomes, , (b) genes are linked and located on same chromosomes, , (c) genes are located on non homologous chromosomes, , (d) All the above, , When dominant and recessive alleles express itself together, , it is called, , (a) codominance (b) dominance, , (c) amphidominace (d) pseudodominance, , A gene is said to be dominant if, , (a) it expresses its effect only in homozygous state, , (b) it expresses its effect only in heterozygous condition, , (c) it expresses its effect both in homozygous and, heterozygous condition, , (d) it never expresses its effect in any conditions, , Harmful mutations does not get eliminated from gene pool, , because, , (a) theyare recessive and carried by homozygous individuals., , (b) they are recessive and carried by heterozygous, individuals., , (c) they are formed repeatedly., , (d) they show genetic drift., , Suppose that in sheep, a dominant allele (B) produces black, , hair and a recessive allele (b) produces white hair. If you saw, , a black sheep, you would be able to identify, , (a) its phenotype for hair colour., , (b) its genotype for hair colour., , (c) the genotypes for only one of its parents., , (d) the genotypes for both of its parents., , What is the probability that a cross between a true-breeding, , pea plant with smooth seeds and a true-breeding pea plant, , with wrinkled seeds will produce F, progeny with smooth, , seeds ?, , (a) 1/2 (b) 1/4, , (c) 0 (d) 1

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10., , 12., , 13., , 14., , 15., , Two organisms that are true-breeding for a certain genetic, characteristic are mated and their offspring analysed. Which, of the following statements about this situation is true?, , (a) Both parents are homozygotes., , (b) The offspring are cither all homozygotes or all, heterozygotes., , (c) The offspring represent the F, generation and the gametes, produced by the offspring will carry only one allele for, this gene., , (d)_ All of the above, , Consider a gene that has two alleles and shows complete, , dominance. When two heterozygotes for this gene breed, they, , have a 25% chance of producing a homozygous recessive, offspring. The next time they breed, what are the chances that, they will once again have a homozygous recessive progeny?, , (a) 0% (b) 25%, , (c) 75% (d) 100%, , In a particular plant, two genes control leaf shape and color., , Round leaves (R) are dominant to jagged leaves (r). Yellow, , fruits (Y) are dominant to white fruits (y). A true-breeding, , round-leaved, yellow-fruited plant is mated with a jaggedleaved, white-fruited plant. What are the genotypes of the, plants involved in this cross ?, , (a) RRYY =x RRYY (b) RRYY = rryy, (c) RrYy x RrYy (d) RrYy = rryy, The exposure of X-rays enhances the frequency of, (a) linkage (b) crossing-over, , (c) pairing of chromosomes (d) segregation, , In the F, generation of a dihybrid cross between yellow, round, , seeded and green, wrinkled seeded pea plants, 17 out of 254, , pea seeds were green and wrinkled. Other seeds were:, , Yellow and round; green and round; yellow and wrinkled., , What do these results indicate ?, , (a) Crossing over has occurred., , (b) Green and wrinkled are both recessive characters., , (c) The alleles for green and wrinkled are linked., , (d) The allele for green is recessive but not the allele for, wrinkled., , Why is the allele for wrinkled seed shape in garden peas, , considered recessive ?, , (a) It “recedes” in the F, generation when homozygous, parents are crossed., , (b) The trait associated with the allele is not expressed in, heterozygotes., , (c) Individuals with the allele have lower fitness than that, of individuals with the dominant allele., , (d) The allele is less common than the dominant allele., (The wrinkled allele is a rare mutant)