Ncert – class 10- science – Chapter 8 – Heredity and Evolution2 Welcome to your Ncert - class 10- science - Chapter 8 – Heredity and Evolution2 1. Select the incorrect statement. The various forms of genes occupying a locus on homologous chromosomes are called alleles. Locus is the position on chromosomes were genes are located. Each character of an individual is controlled by a unit factor. During gamete formation, the alleles do not segregate, so that each gamete receives both the pair of alleles. None 2. Which of the following is the reason for the appearance of new combinations of characters in the F2 progeny? The tall/short and round/wrinkled seed traits are independently inherited The tall/short and round/wrinkled seed traits are not independently inherited None of these The tall/short and round/wrinkled seed traits are linked None 3. Two pea plants one with round green seeds (RRyy) and another with wrinkled yellow (rrYY) seeds produce F1 progeny that have round, yellow (RrYy) seeds. When F1plants are selfed, the F2 progeny will have a new combination of characters. Choose the new combination from the following. (i) Round, yellow(ii) Round, green(iii) Wrinkled, yellow(iv) Wrinkled, green (i) and (iii) (ii) and (iii) (i) and (ii) (i) and (iv) None 4. Which of the following statements about natural selection are correct?(i) Natural selection tends to increase the characters that enhance survival and reproduction.(ii) Individuals with better adaptive ability will produce more progeny.(iii) Was considered as a mechanism of evolution by Darwin. (i) and (ii) only (i) and (iii) only (iii) only (i), (ii) and (iii) None 5. In human beings, the statistical probability of getting either a male or a female child is 50:50. Which of the following is the cause behind it? None of these Both A and B. The ratio of male gametes containing X chromosome and those containing Y chromosome is 50:50. The sex of an infant is determined by the type of sex chromosome contributed by the male gamete. None 6. What are the differences between inherited and acquired characters? Inherited characters - Characters appearing in an individual's lifetime and can be transmitted to next generation. Acquired characters - Characters appearing in an individual's lifetime but cannot be transmitted to next generation. Inherited characters - Characters that are passed on from offspring to parents. Acquired characters - Characters appearing in an individual's lifetime and can be transmitted to next generation. Inherited characters - Characters appearing in an individual's lifetime but cannot be transmitted to next generation. Acquired characters - Characters that are passed on from parents to offspring. Inherited characters - Characters that are passed on from parents to offspring. Acquired characters - Characters appearing in an individual's lifetime but cannot be transmitted to next generation. None 7. A woman has only daughters. Which of the following is the suitable explanation for it? The man produces sperms with either X and Y chromosomes but only the sperms with X chromosomes are viable. The man produces sperms with either X and Y chromosomes but only the sperms with Y chromosomes are viable. The man produces sperms that have only X chromosomes and all are viable. The man produces sperms with either X and Y chromosomes and all are viable. None 8. If in a garden pea plant, a cross is made between red-flowered (RR) and white-flowered (rr) plants. What will be the phenotypic ratio in F2 generation? 3 : 1 1 : 3 1 : 2 : 1 9 : 3 : 3 : 1 None 9. Study the following and select the correct statements.(I) F1 progeny is the first hybrid generation and progeny resembled either of the parents.(II) F2 progeny is a resultant hybrid generation of cross-pollination among F1 progeny and progeny showed both dwarf and tall plants.(III) F2 progeny is a hybrid generation, produced by selfing F1 hybrids and progeny contained both dwarf and tall plants.(IV) The proportion of probability of plants that dwarf was 1/4 that of the F2 plants while 3/4th of the plants were tall. I, II, III, IV I, II, IV I, III, IV III, IV None 10. Choose the correct answer from the alternatives given.In a certain plant, yellow fruit colour (Y) is dominant to green fruit colour (y) and round shape (R) is dominant to oval shape (r). The two genes involved are located on different chromosomes.Which of the following is correct for the condition when plant YyRr is back crossed with the double recessive parent? 9 : 3: 3: 1 Ratio of Genotypes only 1: 1: 1: 1 Ratio of Phenotypes only 1: 1: 1: 1 Ratio of Phenotypes and Genotypes 9:3:3:1 Ratio of Phenotypes only None 11. With respect to the Darwin's theory of natural selection, which of the following is true for the organisms that are best suited to their environment? Are the fastest organisms Are most likely to survive and reproduce Are most likely to live the longest Are most likely to evolve None 12. Speciation does not takes place due to ________. Mutation Genetic variation Geographic isolation Reduced gene flow None 13. 'Feather was used for insulation in cold weather but later, they become useful for flight'. This statement describes: Speciation Genetic variation All of the above Evolution by stages None 14. Which one of the following statements is incorrect? Alleles are different forms of the same gene. Alleles are non-heritable. Alleles code for different isoforms of a protein. Alleles are present at the same locus. None 15. Experiment to prove that synthesis of organic compounds formed the basis of origin of life was performed by : Haldane Miller Oparin Fox None 16. Match the following lists and choose the correct option. List IList IIA. Genetic changes1. Homologous organB. Independent inheritance2. FossilC. Natural selection3. Analogous organD. Dihybrid ratio4. XY5. 9 : 3 : 3 : 1E. Male human beings5. 9 : 3 : 3 : 14F. Wing of a bat and a wing of a bird6. DarwinG. Remnant of ancient animals7. MendelH. Arm of a man and wing of a bird8. DNA copying A- 7, B- 8, C- 6, D- 5, E- 4, F- 3, G- 2, H- 1 A- 8, B- 7, C- 6, D- 5, E- 4, F- 3, G- 2, H- 1 A- 8, B- 6, C- 7, D- 5, E- 4, F- 3, G- 2, H- 1 A- 8, B- 7, C- 6, D- 5, E- 4, F- 2, G- 3, H- 1 None 17. Which of the following statements is/are correct? Mendel's experiments gave us the mechanism for the inheritance of traits from one generation to the next. Both None Mendel's findings remained unknown until these were rediscovered. None 18. Some green beetles appear among the red beetle because Beetles become green by accumulating chlorophyll from the green leaves that they eat. Beetles change colour from red to green with change of season Natural variations occur during sexual reproduction. Red beetles mimic green colour of leaves whenever they see crows None 19. A cross between a tall pea plant and dwarf pea plant resulted tall progenies in F1 generation, because Dwarfness is a dominant trait. Tallness is a recessive trait. Neither 'T' or 't' governs stem height. Tallness is a dominant trait. None 20. According to the theory of acquired inheritance which one is correct? All of the above If a man loses his hand, then his children will also be missing a hand. Organisms are able to bring about a change in their phenotype. Changes in phenotype are passed on by way of the genotype to the next generation. None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
