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

Define changing body composition - age related functional, Define Changing ...

Define Changing Body Composition and Techniques for Measuring Body Composition? Changing body composition has been suggested as a pathway to explain age-related functional decl

Difference between sexual gametes and spores, Q. What is the difference bet...

Q. What is the difference between sexual gametes and spores? Do humans present sexual gametes or spores? Sexual spores are structures generated from meiosis with ploidy number

What is stem cell therapy, What is Stem cell therapy Most defects / dis...

What is Stem cell therapy Most defects / diseases treated by stem cell therapy are not genetic in origin so the therapy will have no impact on gene pool in terms of change in f

Describe nerve cells, In eukaryotes possibly the most rapid and complex sig...

In eukaryotes possibly the most rapid and complex signaling is mediated through nerve impulses.  The Nerve  cells  (neurons)  consist  of  a cell  body  with  numerous projections

Define type of instruments used in spectral techniques, Define Type of Inst...

Define Type of Instruments used in Spectral Techniques? A wide range of instruments are available, possessing a combination of features but there is no rigid classification of

Endocrine glands - gastro-intestinal mucosa, GASTRO-INTESTINA L MUCOSA - ...

GASTRO-INTESTINA L MUCOSA - It develops from the endoderm of the embryo. Inner most layer of the wall of the alimentary canal is called mucosa. Certain cells of the mucosa

Explain indications for surgery of total anomalous, Explain Indications for...

Explain Indications for Surgery of Total Anomalous pulmonary Venous Connection ? Once TAPVC is diagnosed in a neonate with symptoms, operation should be undertaken immediately.

Synergistic contribution of malnutrition to child mortality, Explain Synerg...

Explain Synergistic Contribution of Malnutrition to Child Mortality? The synergistic contribution of malnutrition to child mortality is consistent across populations and can be

Dissection, a 6th grade student friendly definition?

a 6th grade student friendly definition?

Purpose of evaluation, PURPOSE OF EVALUATION: The purpose of  evaluati...

PURPOSE OF EVALUATION: The purpose of  evaluation of service is to answer the questions, "To what extent and how well did the programme meet the objectives of  the service?'

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