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

Define the consequences of obesity, Define the Consequences of Obesity? ...

Define the Consequences of Obesity? Obesity has a number of adverse effects and is a risk factor for several problems as highlighted in Figure. It is a risk factor for all caus

How vitamin k used to prevents bone loss, How Vitamin K used to Prevents bo...

How Vitamin K used to Prevents bone loss? Vitamin K is known to inhibit bone loss through inhibiting effect on osteoclast formation. Thus, adequate levels of vitamin K must be

Differentiate between sterilization and disinfection, Q. Differentiate betw...

Q. Differentiate between sterilization and disinfection? 1) Sterilization is defined as freeing the object or substance from all life of any kind. It is the process by which a

Explain the neurological and sensory system, Neurological and Sensory Syste...

Neurological and Sensory System There are three neurological systems: sensory, motor and autonomic. Sensory system consists of sensory receptors, sensory nerve fibres. Differen

State the term in broad - lunule, State the term in broad - Lunule. In ...

State the term in broad - Lunule. In sand dollars, notches or holes which pass through the body of the animal. Their function is not fully understood though may be involved in

Explain the expansion of the universe, Using the Raisin Bread model from th...

Using the Raisin Bread model from the textbook, describe the expansion of the universe. Do the galaxies expand also?

What effect does alcohol have on reaction time, (a) What effect does alcoho...

(a) What effect does alcohol have on reaction time? (b) What other short-term effects does alcohol have?  (c) What long-term effects can result from an exce

Explain the techniques of surgical correction , Explain  the Techniques of...

Explain  the Techniques of Surgical Correction ? Techniques of Surgical Correction proximal Dissection (De Bakey type I and IZ or Stanford A) Monitoring lines are insert

Explain diseases of pericardium, Q. Explain Diseases of pericardium? Pe...

Q. Explain Diseases of pericardium? Pericardium is the sac covering the heart. Pericardium consists of two layers-the visceral pericardium (epicardium) and the parietal pericar

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