Question

Define the following terms in simplified short manner-

1. polyploidy
2. polyteny
3. restitution nucleus
4. exine

Answer 1

1. Polyploid cells and organisms are those containing more than two paired (homologous) sets of chromosomes.
2. The condition of a chromosome, nucleus, or cell in which the DNA has repeatedly replicated, without subsequently separate
3. A single nucleus formed following failure of the chromosomes to separate properly at anaphase and hence containing, say, twice the expected chromosome number,
4. The exine, or outer layer, is composed of a highly decay-resistant chemical called sporopollenin which is present in outside of pollen grain