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

What is the importance of vitamin B2, What is the Importance of vitamin b2 ...

What is the Importance of vitamin b2 As a prosthetic group of the flavin enzymes, vitamin B 2 is involved in the reactions of almost all nutrients of plants and animals. They

Common features of eye and limb development, Common Features of Eye and Lim...

Common Features of Eye and Limb Development A comparison of the embryonic development of the very much different organs, the eyes and the limb, points to various interesting

Explain total anomalous pulmonary, Explain Total Anomalous pulmonary Venous...

Explain Total Anomalous pulmonary Venous Connection (TAPVC) ? In this congenital anomaly there is no direct communication between the pulmonary veins and the left atrium. All

Resource use of biodiversity, Biodiversity is multiple resource based offer...

Biodiversity is multiple resource based offering us a range of products, materials and services. Our survival and well being of man-kind is directly dependent on biodiversity. Biod

Procedures for diagnosis - electron microscopy, Direct demonstration of the...

Direct demonstration of the causative agent by electron microscopy (EM): Where facilities for electron microscopy are available and a viral disease is suspected, presence o

What are the digestive functions of the liver, What are the digestive funct...

What are the digestive functions of the liver? Besides making bile for release in the duodenum, the liver has other digestive functions. The venous network that absorbs nutr

What is the gas exchange unit of the mammalian lungs, Q. What is the gas ex...

Q. What is the gas exchange unit of the mammalian lungs? The gas exchange units of the mammalian lungs are the alveoli. Q. What is the physical process through which gas ex

Phylum mollusca, what is salen and its characterstics

what is salen and its characterstics

What are the part of the musculoskeletal system, Which are the organs that ...

Which are the organs that are part of the musculoskeletal system? The main organs and tissues that are part of the musculoskeletal system in humans are the cartilages, the bone

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