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

Foot-and-mouth disease - viral disease, F o o t - a n d - m o u ...

F o o t - a n d - m o u t h disease Foot-and-mouth disease (FMD) is an extremely contagious viral disease of cloven footed animals most notably cattle, pig and she

Explain the principle or theory of biuret method, Explain the Principle or ...

Explain the Principle or Theory of biuret method? If a strongly alkaline solution of Biuret is heated with very dilute copper sulphate, a violet colour is obtained. The substan

Define preoperative nutritional care during surgery, Define Preoperative Nu...

Define Preoperative Nutritional Care during Surgery? It can be provided only to prospective candidates of elective surgery and is not feasible for emergency cases. Preoperative

How to predict that a decrease in co2, Jennifer has the "stomach flu" that ...

Jennifer has the "stomach flu" that is going around campus and has been vomiting profusely for the past 24 hours. Not only has she been unable to keep down fluids or food but she h

Lungs - respiratory organs, Lungs - Respiratory Organs In arachnid art...

Lungs - Respiratory Organs In arachnid arthropods such as scorpion and spider, respiration takes place by means of book lungs. There are four pairs of these structures in the

Mendel''s second law not for two or more phenotypical traits, Why is not Me...

Why is not Mendel's second law always valid for two or more phenotypical traits of an individual? The Mendel's second law, or the law of the independent assortment, is valid fo

Medical research - conservation of wildlife, Medical Research - Conservatio...

Medical Research - Conservation of Wildlife  Many animal species are used to test drugs and vaccines and to increase our understanding of human health and disease. The nine-b

Find out the electric potential, Find the electric potential, taking zero a...

Find the electric potential, taking zero at infinity, at the upper right corner (the corner without a charge) of the rectangle in the figure. (Let y = 3.7 cm and x = 6.7 cm.)

Explain barrier techniques - protective clothing, Q. Explain Barrier techni...

Q. Explain Barrier techniques - Protective clothing? Protective outerwear is worn to reduce exposure to debris in spatter. Clinic jackets should have long sleeves, a high neck,

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