Question

Who proposed the Necrohormone (Neochromosome) Theory and in what year?

Options

• Leeuwenhoek in 1719

• Haberlandt in 1933

• Haberlandt in 1921–22

• Kappert in 1933

Answer 1

The Necrohormone (Neochromosome) Theory was proposed by Haberlandt in 1921–22. According to this theory, degenerating cells of the nucellus release a stimulus called necrohormone that causes adjacent nucellar cells to divide and form adventive embryos, explaining the mechanism of nucellar polyembryony.