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

Do echinoderms present internal or external fecundation, Do echinoderms pre...

Do echinoderms present internal or external fecundation? Is there sex division among individuals? The fecundation in echinoderms is external; gametes are liberated in water whe

Prokaryotic cell, whatis a prokaryotic cell? explain its structure and desc...

whatis a prokaryotic cell? explain its structure and description with images

Causes of diabetic ketoacidosis, Q. Causes of Diabetic Ketoacidosis? Th...

Q. Causes of Diabetic Ketoacidosis? The causes of Diabetic Ketoacidosis (DKA) are the following: - Missing of insulin injection - Infection - Trauma (injury) - Myoc

Telophase of karyokinesis, - The chromosomes at each pole uncoil and elonga...

- The chromosomes at each pole uncoil and elongate to form the chromatin. - A nucleolus reappears at each pole. - Spindle fibers and asters disappear and centrioles split. - A nu

Define use of soy protein concentrates in meat products, Define Use of Soy ...

Define Use of Soy Protein Concentrates in Meat products? This area probably represents the most important application of soy protein concentrates (SPC) in the food industry. SP

What is kingdom protista in diversity of life, What is Kingdom Protista in ...

What is Kingdom Protista in diversity of life? Members of Kingdom Protista are grouped separately from the other eukaryotic kingdoms because most of the organisms have a unicel

Brasseler endo extractor tube-endodontics principles, Brasseler Endo Extrac...

Brasseler Endo Extractor tube Insert H file buccally and lingually and remove silver by friction.If I can't remove use solvent to desolve cement If the tip of silver not appear

Homestasis, why does an organism internal environment change

why does an organism internal environment change

The human abo blood type codominant alleles a and b, The human abo blood ty...

The human abo blood type codominant alleles a and b are dominant to O. A man with blood type B and women with blood type A could potentially have children with which of the followi

Pre-embryonic development, Pre-Embryonic Development We had said in t...

Pre-Embryonic Development We had said in the starting of the unit that prenatal development can be divided into two phases, embryonic and foetal. The embryonic phase of devel

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