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

Issues impacting health and development, Issues Impacting Health and Develo...

Issues Impacting Health and Development Poverty and malnutrition are the leading causes of high maternal and child mortality rates in developing countries. Together, they seri

Limitations of doppler echocardiograph, Though  it has bees suggested that ...

Though  it has bees suggested that Doppler echocardiography may be useful for non-invasive determinations of  stroke volume and cardiac output, it  should be recognized that th4re

What is bone remodeling, Bone Remodeling Bone remodeling differs from t...

Bone Remodeling Bone remodeling differs from the other means of bone structure alteration in that osteoblasts and Osteoclasts do not act independently but are coupled and bone

Distribution of stomata, Distribution of Stomata There are two paramet...

Distribution of Stomata There are two parameters normally used for expressing the distribution of stomata. Stomatal frequency: The number of stomata per unit area

Elaborates congenital aortic stenosis in details, Elaborates Congenital Aor...

Elaborates Congenital Aortic Stenosis in details? More common in males (4: 1). High incidence of Bicuspid Aortic valve. Murmur present from early infancy and sometimes at birth

How hermaphrodite species present cross-fecundation, Is it possible for a h...

Is it possible for a hermaphrodite species to present cross-fecundation? There are hermaphrodite species of animals and plants that present cross-fecundation mainly because of

Explain the assessing and monitoring of peri-implant, Explain the assessing...

Explain the assessing and monitoring of peri-implant The parameters used for assessing and monitoring the peri-implant conditions need to be understood and applied judiciously

Comparison between metamorphosis in amphibians and insects, Comparison betw...

Comparison between Metamorphosis in Amphibians and Insects You may have realized that the metamorphic process in amphibians and insects show certain fundamental similarity. M

What is mefloquine, What is Mefloquine Mefloquine is taken once weekly,...

What is Mefloquine Mefloquine is taken once weekly, but recent reports of serious psychiatric adverse effects have prompted the manufacturer, along with the FDA, to strengthen

Cutin, CUTIN It is a lipid formed by polymerization and cross-esterific...

CUTIN It is a lipid formed by polymerization and cross-esterification of hydroxy fatty acids. Cutin occurs inside outer epidermal walls of plant surfaces as bringing agent t

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