Operculum - seed appendages, Biology

Assignment Help:

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.


Related Discussions:- Operculum - seed appendages

Aschelminthes, in what part of the human body aschelminthes found?

in what part of the human body aschelminthes found?

Obtain half their genes from one parent, If children obtain half their gene...

If children obtain half their genes from one parent and half from the other parent, why aren't siblings identical?

Explain unresorbable barriers - root perforation, Explain Unresorbable Barr...

Explain Unresorbable Barriers - Root Perforation MTA exhabits excellent tissue biocompatible non resorbable barrier and restorative material. It represents an extraord

Describe the theory of darwins, Describe the theory of Darwin's? Most s...

Describe the theory of Darwin's? Most scientists today accept the theory that living organisms have evolved according to the concept that was first proposed by Charles Darwin i

Zoonotic diseases-influenza, Influenza Influenza is an acute infectious di...

Influenza Influenza is an acute infectious disease caused by influenza viruses of genus Orthomyxovirus in family Orthomyxoviridae. The name Influenza is derived from an Italian ph

List some differences between a bacteria and a virus, Question 1: (a) L...

Question 1: (a) List some differences between a bacteria and a virus? (b) Define‘Swine Flu'. List the main types of ‘Swine Flu' viruses? (c) Describe the preventive measures

What is radiographic template, What is Radiographic Template Radiograp...

What is Radiographic Template Radiographic Template : You should always use it while taking a panoramic radiograph of the patient. It is done to counter the effect of magnific

What is meant by the law of use and disuse, What is meant by the law of use...

What is meant by the law of use and disuse and by the law of the transmission of acquired characteristics? As per to the law of use and disuse the characteristics of a body var

The number of electrons in their outer energy level, The bonding geometry o...

The bonding geometry of C,O,N is determined by- Select one: a. The number of electrons in their outer energy level b. SP3 hybridization of orbitals in the valence shell

Insulation by fur and feathers, Normal 0 false false false ...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd