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

Describe cardiac rewabilptation and its various effects, Describe cardiac r...

Describe cardiac rewabilptation and its various effects ? A survival benefit cannot be attributed solely to exercise training because many studies involved multifunctional inte

How to facilitate information transfer during transcription, How is energy ...

How is energy used to facilitate information transfer during transcription?

INHERITANCE, how is the problem of chromosome shortening addressed in eukar...

how is the problem of chromosome shortening addressed in eukaryotic organisms and how aging might be related to the problem

Characteristic of callus, Characteristic of Callus The most important ...

Characteristic of Callus The most important characteristic of callus from a functional view point is that abnormal growth has the potential to develop normal roots, shoots and

Explain why methionine is the first amino acid, Explain why methionine is t...

Explain why methionine is the first amino acid in every growing polypeptide. The tRNA that pairs with the start codon on mRNA carries methionine. RNA having ribose; DNA contain

What are some prophylactic measures against hiv infection, What are some pr...

What are some prophylactic measures against HIV infection? The major prophylactic measures against HIV infection are: the use of condoms in sexual relations, not to share syrin

Ventilation of tracheal system - diffusion, Ventilation of Tracheal System ...

Ventilation of Tracheal System - Diffusion Gaseous exchange due to diffusion generally takes care of the oxygen needs of most small insects. Similarly fairly large but inactiv

Vertebrates, characterstics and classification of vertebrates

characterstics and classification of vertebrates

Mixed aortic stenosis and regurgitation, Mixed Aortic Stenosis and Regu...

Mixed Aortic Stenosis and Regurgitation :  The combined aortic valve stenosis and regurgitation may be of congenital or acquired aetiology, as in aortic stenosis. Most common

What is dry mass, What is dry mass? When biomasses are compared often t...

What is dry mass? When biomasses are compared often the method of dry mass is used. The dry mass is the total mass less the water mass of an individual. The total mass is also

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