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

Duodenum participating in extracellular digestion, Q. Besides the liver whi...

Q. Besides the liver which is the other adnexal gland of the digestive system that releases substances in the duodenum participating in extracellular digestion? The other adnex

Inadequate dietary intake - cause of anaemia is dietary, Define Inadequate ...

Define Inadequate Dietary Intake - cause of anaemia is dietary? The commonest cause of anaemia is dietary inadequacy of iron. The dietary intakes arc usually half of the recomm

What is the determination of vitamin B2, What is the Determination of vitam...

What is the Determination of vitamin B 2 In the chemical method, the yellow-green fluorescence of aqueous solution of riboflavin is measured. In the microbiological assay, tur

Secondary production - ecosystem, Secondary Production - Ecosystem Th...

Secondary Production - Ecosystem The net primary production is the only energy available to consumers or heterotrophs including man. Herbivores such as cow or deer gaze upon

Preservation of tooth structure, Q. Preservation of Tooth Structure? Fi...

Q. Preservation of Tooth Structure? Fixed partial dentures have been considered the standard of treatment prior to advent of implant therapy. However, to obtain optimal esthe

How does the swim bladder of fishes work, How does the swim bladder of fish...

How does the swim bladder of fishes work allowing fishes to control their depth under water? From Hydrostatics it is called that an object does not sink if its density is equal

Population distribution, Population Distribution - Population Parameters an...

Population Distribution - Population Parameters and Regulation Dispersion or distribution refers to the pattern of distribution of individuals of a population. As shown in Fig

Professional guidance in diabetes mellitus, Counselling refers to professi...

Counselling refers to professional guidance in resolving personal conflicts and emotional problems. Counselling is a process which enables a person to identify problems and find a

Uptake of ammonia, Uptake of Ammonia Ammonia (NH 3 ) diffuses freely a...

Uptake of Ammonia Ammonia (NH 3 ) diffuses freely across biological membranes according to its concentration gradient. However, ammonium (NH + 4 ) ion requires a specific tra

Man-made disasters- nuclear disasters, Among all the environmental disaster...

Among all the environmental disasters that might be caused by humans, nuclear disasters have the greatest potential of causing severe damage to life property. The released as a con

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