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

Explain subclavian flap aortoplasty, Explain Subclavian Flap Aortoplasty ? ...

Explain Subclavian Flap Aortoplasty ? Initial steps are same as for resection and end-to-end anastomosis. After exposing a the entire length of intra thoracic segment of left s

Describe what is respiration in dynamic auscultation, Describe what is Resp...

Describe what is Respiration in Dynamic Auscultation ? a) S 2 : Splitting of S 1 is audible during inspiration. b) Diastolic sounds and Ejection sounds: Inspiration augment

Explain covalent structure of rna, Like  DNA RNA  is  a  long  polymer  hav...

Like  DNA RNA  is  a  long  polymer  having  of  nucleotides joined by 3'5' phosphodiester  bonds. Furthermore, there are some differences: ?   The bases in RNA are adenine abbr

Explain precautions for gram staining of bacterial cultures, Explain Precau...

Explain Precautions for Gram Staining of Bacterial Cultures? 1. The dilutions should be chosen on the basis of expected counts in the food sample. 2. Food should be kept in

Acid rain, The Phenomenon of acid rain was first introduced by Rober Angus ...

The Phenomenon of acid rain was first introduced by Rober Angus smith in 1852. Is means presence of excessive acids in rain water? Acid rain is a form of precipitation (rain, sn

Describe the method of molecular photo copying, Question 1: "Plant tiss...

Question 1: "Plant tissue culture now has direct commercial applications" Explain. Describe plant tissue culture Illustrate importance of plant tissue culture Sho

Incomplete dominance (1:2:1), INCOMPLETE DOMINANCE (1:2:1) Sometimes tw...

INCOMPLETE DOMINANCE (1:2:1) Sometimes two genes of allelomorphic pair do not show dominant-recessive relationship, but when present simultaneously (or come together), they sho

Normal color vision- color blindness, If a color blind man marries a woman ...

If a color blind man marries a woman pure for normal color vision, it's probable that one of the below situations may result. Is it possible that a) All the children would be

Define antioxidant activity of manganese, Define Antioxidant Activity of ma...

Define Antioxidant Activity of manganese? As Mn is a component of mitochondrial Superoxide Dismutase (SOD), it can protect against oxidative damage. In-vitro experiments have i

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