Chapter 24, Problem 1MCQ

Summary Introduction

Introduction:

Plants are immobile so they have to seek other vector’s help for their sexual reproduction. Sexual reproduction in plants is of two types: meiosis and fertilization. In meiosis rearrangement of genes and reduction in chromosomal number take place while in fertilization reduced number of chromosomes is restored to produce a diploid cell.

Answer to Problem 1MCQ

Correct answer:

Meiosis results in the new gene combination in sexual reproduction of plants. Therefore, option b is correct.

Explanation of Solution

Reason for the correct statement:

The meiosis is a type of sexual reproduction in plants. Two division meiosis I and meiosis II occur to complete cell division and to produce gamete. Gene recombination occurs in meiosis I phase.

Hence, option b is correct.

Reasons for incorrect statements:

Option (a) is given as “Mitosis.” Mitosis is a kind of asexual reproduction in mitosis daughter reproduce from one mother cells, another parent is not required for mitosis. Gene combination occurs in sexual reproduction only. Hence, it is a wrong answer.

Option (c) is given as “Grafting.”  Grafting is a technique of artificial reproduction. In grafting process, the tissues are taken out from the plant and kept adjacent in a way that they grow together. It is not a kind of sexual reproduction hence gene combination cannot take place. Hence, it is a wrong answer.

Option (d) is given as “Both b and c are correct.” As in meiosis, gene combination takes place in meiosis but grafting is not a type of sexual reproduction, and gene combination occurs only in sexual reproduction. Hence, it is a wrong answer.

Hence, options (a), (c), and d) are incorrect.

Conclusion

Genes from both parents combine to produce a new gene combination which occurs only in sexual reproduction. Meiosis is a kind of sexual reproduction, while mitosis and grafting fall in the category of asexual reproduction and artificial reproduction respectively.