Principles of Inheritance and Variation Question 16

16. A cell at telophase stage is observed by a student in a plant brought from the field. He tells his teacher that this cell is not like other cells at telophase stage. There is no formation of cell plate and thus the cell is containing more number of chromosomes as compared to other dividing cells. This would result in

[2016]

(a) Aneuploidy

(b) Polyploidy

(c) Somaclonal variation

(d) Polyteny

Show Answer

Answer : b

Hints & Solution

(b) This phenomenon is known as polyploidy, wherein the cells contain more than two paired (homologous) sets of chromosomes. Polyploidy is often seen in the case of plants. The major cause of polyploidy is the non-disjunction of sister chromatids during meiotic recombination. This condition is actually useful in development of new crop varieties.