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

Treatment of heart failure, Over the past decade, the conceptual understand...

Over the past decade, the conceptual understanding of heart failure has changed significantly. Several large clinical trials have demonstrated that non-pharmacological and pharmaco

Why iron is required as a part of haemoglobin, Why Iron is required as a pa...

Why Iron is required as a part of haemoglobin? As a part of haemoglobin, iron is required for the transport of oxygen, to all cells in the body. Thus, haemoglobin is critical f

Malarial disease, Malarial disease Malaria is a disease known since ...

Malarial disease Malaria is a disease known since ancient times almost from 5th century B.C. The word malaria actually means bad air. It was believed that malaria is c

Avian influenza (ai), A v i a n influenza (AI) One of only two 'Lis...

A v i a n influenza (AI) One of only two 'List A' diseases of poultry targeted for emergency disease control measures by OIE, avian influenza is a highly contagious viral d

State the prevention of campylobacteriosis diseases, State the prevention o...

State the prevention of Campylobacteriosis Prevention: the various ways to prevent campylobacteriosis are: Wash hands before preparing foods. Wash hands immediatel

Difference between distant object and near object, Difference between Dista...

Difference between Distant object and Near object - Distan t object Near object   1. Parallel light reaches to eye.   2. Ci

Define the characteristics that are seen in rickets, Define the characteris...

Define the characteristics that are seen in Rickets? The following characteristics are seen in fully developed cases of rickets: 1) In case of young infants, delayed closure

Nutrients and the soil, Nutrients and the Soil Early experiments on mi...

Nutrients and the Soil Early experiments on mineral uptake were performed by Hoagland, Stout and Amon in 1923. They showed that minerals were taken up from the soil primarily

PROTOZOA, WHAT IS THE CLASSIFICATION OF PROTOZOA ..

WHAT IS THE CLASSIFICATION OF PROTOZOA ..

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