Morphological nature of endosperm, Biology

Morphological Nature of Endosperm

The morphological nature of endosperm in angiosperms has been a subject of much discussion in evolution. The endosperm in gymnosperms is a gametophytic (haploid) tissue as it develops directly by the continued free nuclear divisions of the functional megaspore. In angiosperms, however, it develops from the primary endosperm nucleus which is normally formed by the fusion of two polar nuclei and a male nucleus and hence it is neither haploid nor diploid but generally triploid. Some workers have suggested that the endosperm in angiosperms is a gametophytic tissue just like those of gymnosperms, the only difference being that its development remains arrested till the entry of the pollen tube into the ovule.

Other embryologists have considered it as a second embryo or a maimed embryo. The most agreeable view regarding the morphological nature of the endosperm in angiosperm is that it is an undifferentiated tissue which shows different degrees of polyploidy. By suppressing the growth of the embryo in a seed, it has been possible to induce triploid shoot bud development in the endosperm. However, truly triploid plants have not been obtained so far.

Posted Date: 1/23/2013 7:03:01 AM | Location : United States







Related Discussions:- Morphological nature of endosperm, Assignment Help, Ask Question on Morphological nature of endosperm, Get Answer, Expert's Help, Morphological nature of endosperm Discussions

Write discussion on Morphological nature of endosperm
Your posts are moderated
Related Questions
Explain about the Biofertilizers Biofertilizers, are the cultures of microorganisms used for inoculating seed or soil or both under ideal conditions to increase the availabilit

Question : (a) Briefly describe what are non degradable pollutants? (b) What do you meant by ichthyosarcotoxic fishes and give two examples of ichthyosarcotoxic fish poiso

What do you mean by Syconoid sponge. Of different sponge architectures, this is intermediate in its complexity. Spongocoel is no longer lined with choanocytes, now located in r

Leaving the deserts as you approach the tropical regions of the earth you will enter the savanna biome, which is a combination of grassland with scattered or clumped trees. These s

Photosynthesis Photosynthesis - the process by which plants utilise energy from sunlight to convert carbon dioxide and water for the synthesis of sugar. This sugar can then be

Respiratory Care on Admission (First two hours) Patient is incubated and ventilator-dependent.  Monitor blood gases hourly and take corrective action immediately.

Explain about the Adequate Intake (AI)? If sufficient data are not available to establish an EAR and hence RDA, the AI is derived instead. The AI is derived from observations o

Describe five different types of gateway vectors that are available, what different functions they can perform, and for what purpose. e.g.  (1) Vector pXXX, (2) function - expre

Differance between pulsus bigerniny or trigeminy and presence of bruit ? Pulsus bigerniny or trigeminy: After every 2nd or 3rd beat respectively there will be a longer inter

Solubility You are aware that gases are soluble in liquid. Solubility of a gas in a liquid depends on the partial pressure, temperature and presence of other solutes. Table