Trending ▼   ResFinder  

NUMERICAL PROBLEMS ON ICSE GENETICS

3 pages, 4 questions, 0 questions with responses, 0 total responses,    0    0
Sumit Roy
Sri Sri Academy (SSA), Kolkata
+Fave Message
ProfileTimelineUploads
 Home > sumitroy >

Formatting page ...

NUMERICAL PROBLEMS ON ICSE GENETICS 1. What type of children will appear in F1 generation if a colour blind man marries with a normal woman? Gene for colour blindness is Xc and gene for normal vision is Xc+. 2. Gene A is dominant over gene a. What will be the phenotypic ratio in the offspring obtained from the following mating?(a) Aa X aa. (b) Aa X AA. (c) Aa X Aa. 3. In humans pointed eyebrows is dominant over smooth eyebrows. Rahul s father has pointed eyebrows but he and his mother has smooth eyebrows. Predict the following:(a) Give the genotype of Rahul. (b) What will be the genotype of his father and mother? (c) If Rahul marries a woman who is heterozygous, what will be the possible genotype of the offspring in the next generation? State the % probability of having homozygous dominant, homozygous recessive and heterozygous dominant. 4. A haemophilic man marries a normal homozygous woman. What is the probability that their daughter will be haemophilic? 5. In a certain mammal curly hair is dominant over straight hair. In a cross between the two in the F 2 generation, three had curly hair and one had straight hair. (a) What would be the genotype of parents? (b) Work out the genetic cross. 6. A cross is made between Tall plant with Yellow seeds (TtYy) and a tall plant with green seeds (Ttyy). What proportion of phenotype would be expected in the offspring to be (a) Tall and green (b) Dwarf and green. 7. A man with AB blood group marries a woman of O blood group. Work out the possible genotype and phenotype of the progeny. 8. A heterozygous Smooth seeded and Red flowered pea plant is crossed with homozygous recessive rough seeded white flowered plant. Determine the progeny. 9. Ravi s parents have normal colour vision but his maternal grandfather is colourblind. Gene for colour vision is located on the X chromosome. (a) Work out a cross, showing the percentage of chances of Ravi and his siblings being colour blind. (b) What is the genotype of mother. (c) State the type of inheritance being shown in the above cross. 10. A haemophilic man marries a carrier woman. Obtain phenotypes of offspring using Punnett square.What is Y- linked inheritance? 11. A normal visioned woman marries a normal visioned man. They have a colour blind child.How can it be explained? Use Punnett square to substantiate your answer. 12. Some dogs bark while trailing while others are silent. The barking trait is due to dominant gene. Erect ears are dominant over drooping ears. What kind of puppies would be expected from the heterozygous erect eared barker mated to a droop silent trailer? 13. A man with blood group A marries a woman with B blood group. Find out the genotypes and the blood groups of their children, when (a) Both parents are heterozygous. (b) Both parents are homozygous. (c) Man is heterozygous and female is homozygous. (d) Man is homozygous and female is heterozygous. 14. Zicco s parents have normal colour vision but his maternal grandfather is colour-blind. Gene for colour vision is located on the X chromosome. (a) Work out a cross showing showing the percent chances of Zicco and his siblings being colour blind, normal or carrier. (b) What is the genotype of his maternal grandfather? 15. A haemophilic man marries a carrier woman. Find out the genotypes of the offspring. 16. Using a Punnett Square, workout the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus. 17. When a cross in made between tall plant with yellow seeds (TtYy) and tall plant with green seed (Ttyy), what proportions of phenotype in the offspring could be expected to be (a) Tall and green. (b) Dwarf and green. 18. A child has blood group O. If the father has blood group A and mother blood group B. Work out the genotypes of the parents and the possible genotypes of the other offsprings. 19. What will be the probability of the children with A blood type if mother has AB blood group and father is heterozygous for B blood group? 20. In humans, brown eyes (B) are dominant over blue (b). A brown- eyed man marries a blue eyed woman and they have three children, two of whom are brown eyed and one of whom is blue eyed. Draw a Punnett square that illustrates this marriage. (a) What is the man s genotype? (b) What are the genotypes of the children? 21. A red (R) colour pea flower is crossed with a white (r) colour pea flower. Predict the following:(a) What type of genetic cross is given above? Justify. (b) What is the nature of offspring in the F1 generation? (c) State the phenotypic ratio and phenotypic % probability of F2 progeny using Punnett square. (d) State the genotypic ratio and genotypic % probability of F2 progeny. (e) State the law enunciated in the above cross. Who proposed the law? 22. A tall (TT) pea plant with red (RR) colour flower is crossed with a dwarf (tt) pea plant with white (rr) colour flower. Predict the following:(a) What type of genetic cross is given above? Justify. (b) What is the nature of offspring in the F1 generation? (c) What are the possible combinations of gametes for the F2 generation? (d) State the phenotypic ratio and phenotypic % probability of F2 progeny using Punnett square. (e) State the genotypic ratio and genotypic % probability of F2 progeny using Punnett square. (f) If a heterozygous F1 offspring is crossed with homozygous recessive parent, what type of cross will it be? State the ratio of such cross. (g) State the law enunciated in the above cross. Who proposed the law? 23. In human beings blue eye colour is recessive to brown eye colour. A brown eyed man has a blue eyed mother. (a) What is the genotype of the man and his mother? (b) What are the possible genotypes of his father? (c) If the man marries a blue eyed woman, what are the possible genotypes of their offspring? 24. A man with blood group A married a woman with B blood group and a daughter with blood group O. Work out the cross and show the possibility of such inheritance. 25. A pure tall plant (TT) is crossed with pure dwarf plant (tt). Draw Punnett squares to show F 1 and F2 generation. Give the phenotype and Genotype of the F1 and F2 generation. 26. A normal visioned woman marries a normal visioned man. They have a colour blind son. How can it be explained? Use Punnet square to substantiate your answer. 27. A heterozygous tall pea plant is crossed with a homozygous dwarf pea plant. With the help of a Punnett square, show the parents and their offsprings Phenotypes and Genotypes. 28. A haemophilic man marries a carrier woman. Obtain phenotypes and genotypes of offsprings using Punnett square. 29. Let Y be the genotypic symbol for the dominant yellow seed colour, symbol y for recessive green seed colour, symbol R for dominant round shape of the seed and symbol r for recessive wrinkled seed shape in the garden pea. Using these symbols, explain Mendel s law of Independent Assortment. 30. Ashok parents have normal colour vision but his maternal grandfather is colour blind. (a) Work out a cross showing percent changes of Ashok and his siblings being colour blind. (b) What is the genotype of his mother? (c) What is the term used for this kind of inheritance? Mention two specialties of such inheritance. 31. A normal woman whose mother was colour blind has a son. Nothing is known of the colour vision phenotype of the father. What is the probability that the son will be colour blind? Prepared by:Mr. Sumit Roy [Asst. Biology Teacher] (9830431393/9874577160/7044929409) Post Graduate Diploma in Environmental Biotechnology (C.U.) M.Sc (Zoology), Gold Medalist of Vidyasagar University, B.Ed E mail: - sumitroy888@gmail.comsumit@ssa.org.in

Formatting page ...

Formatting page ...

 

  Print intermediate debugging step

Show debugging info


 

 

© 2010 - 2025 ResPaper. Terms of ServiceContact Us Advertise with us

 

sumitroy chat