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 the behavioural change communication, Explain the Behavioural chang...

Explain the Behavioural change communication? One of the reasons for the widespread prevalence of PEM in our country is ignorance due to illiteracy, particularly among the fema

Simple or unilayered epithelia, SIMPL E EPITHELIA (UNILAYERED EPITHELIA) -...

SIMPL E EPITHELIA (UNILAYERED EPITHELIA) - 1 .      SIMPLE SQUAMOUS EPITHELIUM (PAVEMENT EPITHELIUM) - It is composed of large flat cells whose edges fit closely toge

Describes the tenants of pangenesis theory, Which of the following best des...

Which of the following best describes the tenants of Pangenesis Theory? A. The hereditary material is composed in every organ/tissue and is transmitted to the next generation b

Explain separation of homologous chromosomes, Q. What are the respective fu...

Q. What are the respective functions of the separation of homologous chromosomes and of the separation of alike chromatids in meiosis? The separation of homologous chromosomes

Discuss in detail about the close head injuries, Discuss in detail about th...

Discuss in detail about the Close Head Injuries Closed-head injuries result from a blow to the head, which can subject the brain to a variety of mechanical forces: Damag

Measurement of the active ingredient in aspirin pills, Medication delivered...

Medication delivered in the form of a pill contains an active ingredient or ingredients. Beside the drug itself, the pill also contains "fillers". The filler has several functions.

What is mitochondrial inheritance?, What is mitochondrial inheritance? ...

What is mitochondrial inheritance? The Mitochondrial inheritance is the passage of mitochondrial DNA molecules (mtDNA) to the offspring. All the stock of mtDNA an individual ha

Explain pedicellaria in brief, Explain Pedicellaria in brief? Defensive...

Explain Pedicellaria in brief? Defensive pincerlike structures found on the surface of echinoderms. They are capable of responding to external stimuli independently from the ma

Eastern/western/venezuelan equine encephalitis, Eastern/Western/Venezuelan ...

Eastern/Western/Venezuelan equine encephalitis This encephalitis causing group of viral diseases of wild birds including pheasants, chickens, turkeys, ducks and pigeons with a

Human diseases caused by bacteria, Q. What are some human diseases caused b...

Q. What are some human diseases caused by bacteria and what are their respective modes of transmission? The major human bacterial infections transmitted by respiratory secretio

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