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

Microbiology of air, Ask question #i need the complete table having the nam...

Ask question #i need the complete table having the names of the diseases their causative agents and their control,caused by air-borne pathogens?

Define general purpose and specialized culture media, Define General Purpos...

Define General Purpose and Specialized Culture Media? General purpose media - These support the growth of many microorganisms. Example: nutrient agar, trypic soy agar etc. S

Define classification of carbohydrates - disaccharides, Define classificati...

Define classification of carbohydrates - Disaccharides? Disaccharides are condensation products of two monosaccharide units joined together by a linkage called glycosidic linka

Section 3.1, Lack of iron in the photic zone of the ocean restricts the siz...

Lack of iron in the photic zone of the ocean restricts the size of plankton population.Iron is what kind of factor for marine plankton?

What is starch , Starch exists in plants as insoluble starch granules in c...

Starch exists in plants as insoluble starch granules in chloroplasts.  Each starch granule   holds   a   combination   of   two   polysaccharide    forms, amylopectin and amylose.

Define abbe condenser of microscope, Define Abbe Condenser of Microscope? ...

Define Abbe Condenser of Microscope? It is present beneath the stage, as shown in Figure. It collects and focuses a cone of light on the slide. Its position can be adjusted ver

Show some evolutionary advantages of animals, Q. What are some evolutionary...

Q. What are some evolutionary advantages of animals with complete digestive tube? The complete digestive tube permits animals to continuously feed themselves without waiting fo

List the heterotrophic nutrition in plants, a) List the a variety of modes ...

a) List the a variety of modes of heterotrophic nutrition in plants. b) Define any two modes giving one example of each.

Define fuel molecules and lipogenesis, Define Fuel Molecules and Lipogenesi...

Define Fuel Molecules and Lipogenesis? Lipogenesis is a collective name for the complex process of producing lipids (fatty acids) from smaller precursor molecules. The synthesi

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