Heredity and evolution Worksheet-19

Heredity and evolution Worksheet-19

True / False:

1. Organisms reproducing by asexual reproduction   show more variation as compared to those reproducing by sexual mode.

2. Variations arising during asexual reproduction are caused due to inaccuracies in DNA copying.

3. Sexually reproducing organisms have multiple alleles for same trait.

4. Gregor Johann Mendel is the Father of Evolution.

5. In case of monohybrid cross with pure variety of plants, the phenotypic ratio obtained in F2 generation is 1:2:1.

6. In case of dihybrid cross involving 2 pairs of contrasting characters, the phenotypic ratio obtained in F2 generation is 9:3:3:1

7. All homozygous traits are denoted by two capital letters.

8. Gametes are always haploid.

9. Genes carry information for producing proteins that control the various body characteristics.

10. Sex of all living organisms is determined by genetic method.

11. Humans have 22 pairs of allosomes and one pair of autosomes.

12. Human females are homogametic.

13. All sperms produced by human male carry X chromosome.

14. Genetic drift can alter gene frequencies in small population.

15. Mutation that alters the DNA sequence is not inherited.

16. Gregor Mendel  proposed that evolution of species occurred by natural selection.

17. Geographical isolation of self pollinated species can result in speciation.

18. Gene flow between the members of a population prevents speciation.

19. Each species is the biggest gene pool possible under natural conditions.

20. Wing of insect and the wing of bat are analogous structures.

Answer:

1. False

Explanation: Organisms reproducing by sexual reproduction   show more variation as compared to those reproducing by asexual mode

2. True

3. True

4. False

Explanation: Gregor Johann Mendel is the Father of Genetics

5. False

Explanation: In case of monohybrid cross with pure variety of plants, the phenotypic ratio obtained in F2 generation is 3:1, while genotypic ratio is 1:2:1

6. True

7. False

Explanation: homozygous dominant trait is denoted by two capital letters whereas the homozygous recessive trait is denoted by two small letters]

8. True

9. True

10. False

Explanation: sex can be determined genetically or non genetically in different organisms

11. False

Explanation: Humans have 22 pairs of autosomes and one pair of allosomes.

12. True

13. False

Explanation: 50 percent of them carry X chromosome while 50percent carry Y chromosomes

14. True

15. False

Explanation: Mutation that alters the DNA sequence is inherited.

16. False

Explanation: Charles Darwin proposed that evolution of species occurred by natural selection

17. False

Explanation: Geographical isolation of cross pollinated species can result in speciation

18. True

19. True

20. True