Obturator - ovule, Biology

Assignment Help:

Obturator - Ovule

An obturator is an outgrowth of the placenta or funicle or integument or style near the micropyle. It is presumed to guide the pollen tube to the micropyle. This tissue is either composed of thin-walled compact tissue or it is made up of loose hairy outgrowths. The cells of the obturator at the ultra structural level, show dense cytoplasm containing a copious number of ER, dictyosomes, and vesicles. The cells of the obturator produce a surface exudate and provide mechanical and chemical guidance to the growing pollen tube.

323_Obturator.png

Figure:  Obturator in Tetragonia tetragonioides


Related Discussions:- Obturator - ovule

What are the five human digestive secretions, Q. What are the five human di...

Q. What are the five human digestive secretions? Which of them is the only pne that does not contain digestive enzymes? The human digestive secretions are: bile, saliva, gastri

Define protein requirements during sepsis, Define Protein Requirements duri...

Define Protein Requirements during Sepsis? Adequate amount of protein is required by these patients to improve immunity against infections, promote recovery, spare lean body ma

Mrna molecule codifies only one kind of protein, Q. An mRNA molecule codifi...

Q. An mRNA molecule codifies only one kind of protein? Eukaryotic cells have monocistronic mRNA, that is each mRNA codifies only one polypeptide chain, Prokaryotes can present

Explain about the supply curve or supply schedule, Explain about the supply...

Explain about the supply curve or supply schedule. The supply curve or schedule shows the total quantity of a good or a service supplied within aggregate, by whole sellers or f

Define some features of penicillium, Define some features of Penicillium? ...

Define some features of Penicillium? The identifying features of Penicillium are: 1. Mycelium consists of colourless, septate and branched hyphae, some of which grow inside

Reciprocal crosses , RECIPROCAL CROSSES Similar results were obtained w...

RECIPROCAL CROSSES Similar results were obtained with reciprocal crosses also. A reciprocal crosses involves the same traits but carried by sexes opposite to those in the origi

Explain treatment options for ailing and failing implants, Treatment option...

Treatment options for ailing and failing implants are varied. The clinician should start conservatively and progress to more aggressive therapy. The overall goal of therapy is

Fuel requirements - deforestation, Fuel Requirements - Deforestation T...

Fuel Requirements - Deforestation The increasing demand for fuel wood is one of the major factors leading to the degradation of the forest ecosystem. Fuel wood is of such majo

Zoonoses disease-ehrlichiosis, Ehrlichiosis The disease is caused by a ric...

Ehrlichiosis The disease is caused by a rickettisia, called Ehrlichia canis. Dogs and man are the reservoir hosts. The infection is transmitted through bite of infected tick, Rhip

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