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

Define the requirements for water, Define the Requirements for Water? T...

Define the Requirements for Water? The body has no provision for water storage; therefore the amount of water lost every 24 hours must be replaced to maintain health and body e

Production diseases, Pr o d u c t i o n Diseases The production...

Pr o d u c t i o n Diseases The production diseases, which were previously referred as metabolic diseases, include diseases like parturient paresis (milk fever), downer

Who are atopic individuals, Atopic individuals are those who are having abn...

Atopic individuals are those who are having abnormal high levels of circulating IgE and more than normal number of oesinophils.

Explain the introduction of history of mart disease, Explain the introducti...

Explain the introduction of history of mart disease? Cardio-vascular diseases (CVD) are the leading causes of death and disability both in the developed and the developing na

How to explain the high level of radiation resistance, Deinococcus radiodur...

Deinococcus radiodurans is a bacterium that was isolated from cooling ponds in and around nuclear power plants. It is highly resistant to ionizing radiation. Propose a hypothesis t

What is eutrophication in ecology explain briefly, What is Eutrophication i...

What is Eutrophication in ecology explain briefly? Freshwater ecosystems demonstrate the close relationship between aquatic and terrestrial ecosystems. Until recently, most peo

Describe class diplopoda and chilopoda in detail, Describe Class Diplopoda ...

Describe Class Diplopoda and Chilopoda in detail? Members of the Subphylum Crustacea and the Subphylum Uniramia have one major characteristic in common. Both groups have biting

Explain keshan disease caused by selenium deficiency, Explain Keshan diseas...

Explain Keshan disease caused by Selenium deficiency? It is a cardiomyopathy (disease of the myocardium, involving heart muscle) that was identified to affect children and wome

Which of following is not true regarding the immune response, Which of the ...

Which of the following is not true regarding the immune response? Answer The immune response uses chemical and phagocytic cells to destroy foreign cells. Once initiated, the immune

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