Operculum - seed appendages, Biology

Operculum - Seed Appendages

The term operculum is applied to a plug-like structure formed in the micropylar portion of the seed by proliferation of cells at the tip of the inner integument or the nucellus. An operculum has been observed in seeds of many monocotyledonous families, such as the Commelinaceae, Musaceae, Lemnaceae and Zingiberaceae, and a few dicotyledonous families like Bignoniaceae and Nymphaeaceae.

In Lemna paucicostata, cells at the tip of the inner integument undergo a remarkable expansion after fertilization and form a dome-shaped, stopper- like operculum. Cells of the operculum are thick-walled and contain an orange-red substance. During germination of the embryo the operculum becomes detached from rest of the seed and facilitates emergence of the embryo.

Posted Date: 1/23/2013 8:08:37 AM | Location : United States







Related Discussions:- Operculum - seed appendages, Assignment Help, Ask Question on Operculum - seed appendages, Get Answer, Expert's Help, Operculum - seed appendages Discussions

Write discussion on Operculum - seed appendages
Your posts are moderated
Related Questions
Explain Saquinavir Saquinavir (SQV, Fortovase, Invirase) - When administered as a single protease inhibitor, a soft-gel preparation (Fortovase) with improved bioavailability an

Explain in detail about the Concomitant squint Concomitant squint is also called comitant squint. It means "I follow you", i.e., in all directions of gazes, the squinted eye fo

EGG S OF EUTHERIA This egg is small & round. The dimeter of human egg is 0.1 mm. It has very little amount of yolk but they are also as alecithal egg. The egg is covered

Define effect on Human chorionic gonadotropin in Pregnancy? Human chorionic gonadotropin (HCG) begins to increase immediately on implantation of the ovum and reaches a peak at

when pollen tube enters the embryo-sac,it has;

Chlorophyll is the pigment in the green plants which absorbs solar energy.   chlorophyll a -  It is a green photosynthetic pigment common to all the photosynthetic organisms.

Explain the Invasive species? Tens of thousands of non-native species have been introduced into the United States of America, with more arriving each year. These species can ha

what are the excretory organs protozoa

What are the respective functions of the separation of homologous chromosomes and of the separation of identical chromatids in meiosis? The separation of homologous chromosomes

Generalised Seizures Generalised seizures are bilaterally symmetrical without focal onset. One subtype, the grand mal attack, is characterised by loss of consciousness and by s