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

Soil pollution, Soil is upper crust of earth which support land plants and ...

Soil is upper crust of earth which support land plants and animals. It is defined as addition of substances to the soil, which adversely affect physical, chemical? And biologica

Explain chemistry and occurrence of phytates, Explain Chemistry and Occurre...

Explain Chemistry and Occurrence of phytates? Most plant foodstuffs contain inositol which is present in the form of inyo-inositol hexakisphosphate i.e. phytic acid and its sal

Describe briefly about the type 1 diabetes, Describe Briefly about the Type...

Describe Briefly about the Type 1 Diabetes? In people with normal weight, Type1 Diabetes is not a major cause of death but it is an important contributor to morbidity and morta

Absorption of lipids, Absorption of lipids Absorption of lipids is qui...

Absorption of lipids Absorption of lipids is quite different from the absorption of monosaccharides and amino acids. Figure shows the process. The free fatty acids, monoglycer

How many cells are in the human body, How many cells are in the human body?...

How many cells are in the human body? According to "The Handy Science Answer Book" noted by the Science and Technology Department of the Carnegie Library of Pittsburgh (1994) th

How sugar play a major role in fermentation, How sugar play a major role in...

How sugar play a major role in Fermentation? The production of chemicals by fermenting several sugars is a very well-accepted science. Its utilize ranges from producing beverag

Long-term responses - behaviour of plants, Long-term responses - Behaviour ...

Long-term responses - Behaviour of Plants Plants alter their course of development to suit the prevailing environmental conditions. For example, leaf maturation and fall, onse

Explain the working of human visual system, Q. Which is the part of the hum...

Q. Which is the part of the human visual system where the receptors that sense light, i.e., the photoreceptor cells, are located? How do those cells work? The photoreceptor cel

Lymphatic vessels, Lymphatic Vessels The function of lymphatic vessel...

Lymphatic Vessels The function of lymphatic vessels is to aid in the return of interstitial fluid to intra-vascular volume. They assist with transport of lipids from th

Db is a standard abbreviation, DB is a standard abbreviation used for the q...

DB is a standard abbreviation used for the quantitative expression of: 1. the density of bacteria in a medium 2. a particular pollutant 3. the dominant Bacillus in a cultu

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