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 food business and food technology, Define Food Business and Food Tec...

Define Food Business and Food Technology? The food business and food technology are practically inseparable. The food business may be characterized as: vulnerable to spoilage,

What are melanocytes, What are melanocytes? Melanocytes are epithelial ...

What are melanocytes? Melanocytes are epithelial cells of the skin particular in secretion of melanin. Melanin is a pigment that besides coloring the skin, the iris of the eye

Define about the paper electrophoresis, Define about the Paper electrophore...

Define about the Paper electrophoresis? In paper electrophoresis the sample is applied to a point on a strip of filter paper or cellulose acetate moistened with buffer solution

State about the halsted reitan battery, State about the Halsted Reitan batt...

State about the Halsted Reitan battery The Halsted Reitan battery, as the procedure came to be known over the years, also has a history. It has been described as a fixed batter

Determine the goal of a bcc programme, Determine the Goal of a BCC Programm...

Determine the Goal of a BCC Programme The overall goal of BCC programs for diabetes mellitus is to promote behaviors that control blood sugar and prevent complications. Thes

Scientific method, SCIENTIFI C METHOD - The scientific approach to exp...

SCIENTIFI C METHOD - The scientific approach to explain a particular phenomenon require a series of organized steps based on common sense. It is called scientific method. A

Explain diseases of pericardium, Q. Explain Diseases of pericardium? Pe...

Q. Explain Diseases of pericardium? Pericardium is the sac covering the heart. Pericardium consists of two layers-the visceral pericardium (epicardium) and the parietal pericar

Light stratification - lake ecosystem, Light Stratification - Lake Ecosyste...

Light Stratification - Lake Ecosystem The penetration of light in water bodies is limited depending on the transparency of water and its ability to absorb light. On the basis

Difference between striated, DIFFERENCE S BETWEEN STRIATED, NON-STRIATED A...

DIFFERENCE S BETWEEN STRIATED, NON-STRIATED AND CARDIAC MUSCLE FIBRES -                      Striated                                                              Non-striat

Define clinical manifestations associated with cancer, Define Clinical Mani...

Define Clinical Manifestations and Nutritional Problems Associated with Cancer? In the previous section we learnt that cancer results in several changes in the metabolism of ca

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