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 single beam and double beam optical path, Define Single Beam and Dou...

Define Single Beam and Double Beam Optical Path? In simpler instruments, a single beam of light passes through the cuvettes and reaches the detector whereas in the double beam

Explain arthritis, Explain Arthritis Arthritis - Oral therapy with doxy...

Explain Arthritis Arthritis - Oral therapy with doxycycline or amoxicillin for 28 days is usually effective for treatment of Lyme arthritis. Patients who have not responded to

Explain micronutrient deficiencies during kwashiorkor, Explain Micronutrien...

Explain Micronutrient deficiencies during kwashiorkor? Almost all the children manifest anaemia (due to iron deficiency) of some degree. Eye signs of vitamin A' deficiency are

Skeleton, how they are joints to each other

how they are joints to each other

Cockroach heart, How last chamber of heart in cockroach receives blood with...

How last chamber of heart in cockroach receives blood without having ostia?

Determine the process of circulatory system, How does the circulatory syste...

How does the circulatory system participate in the functioning of the endocrine system? The circulatory system is fundamental for the performance of the endocrine system. The b

How can coacervates formed of phospholipids or polypeptides, How can coacer...

How can coacervates be formed of phospholipids or polypeptides? Phospholipids are amphipathic molecules, i.e., they present a polar portion and a nonpolar portion. In contact w

Discuss the importance of septa in maxillary sinus, Discuss the importance ...

Discuss the importance of septa in maxillary sinus during a sinus lift or graft surgery. Septa, when present in the maxillary sinus will divide it into sections creating separa

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