Ovule, Biology

Assignment Help:

Ovule

The ovule, also known as the megasporangium is the forerunner of the seed. It consists of a central mound of tissue called the nucellus, which is enveloped by one or two coverings - the integuments. An ovule ready for fertilization consists of nucellar tissue enveloped almost completely by integument(s), leaving a small pore or opening at the apical end.

This opening, called micropyle is the main passage for the entry of the pollen tube into the ovule. This end of the ovule is generally referred to as the micropylar pole and the opposite pole where funiculus is attached is called the chalazal pole. The ovule is attached to the placenta through a stalk-like structure the funiculus. In the nucellus is present the female gametophyte which is commonly referred to as the embryo sac.

 


Related Discussions:- Ovule

Define need of vitamin a during pregnancy period, Define Need of vitamin A ...

Define Need of vitamin A during pregnancy period? All four vitamins (A,C,E and K) have specific functions and a common role for all of them is to preserve the structural and fu

What factors influence whether a person will develop cancer, What factors i...

What factors influence whether a person will develop cancer? Factors contain the person's age, number of exposures to carcinogens, amount of carcinogen in every exposure, and p

Explain aortic valvuloplasty, Q. Explain Aortic Valvuloplasty? Valvar a...

Q. Explain Aortic Valvuloplasty? Valvar aortic stenosis accounts for 4-6 per cent of CHD. LV Outflow Tract obstruction eventually leads to LV dysfunction and congestive heart f

What is meant by saturation or unsaturation of oils and fats, What is meant...

What is meant by saturation or unsaturation of oils and fats? When it is said that a triglyceride is saturated it means that in its molecule the carbon chain is bound in its ma

What are presbyopia and astigmatism, What are presbyopia and astigmatism? ...

What are presbyopia and astigmatism? Presbyopia is the visual impairment in which there is loss of the cililary muscle strength therefore reducing the capability of the crystal

How inadequate breast milk cause protein energy malnutrition, How Inadequat...

How Inadequate Breast Milk cause protein energy malnutrition? Though prolonged breastfeeding of children is the rule in US, the amount of breast milk secreted in poor Indian mo

What are properties that make water special for life, Q. What are the major...

Q. What are the major water properties that make water special for life? The water properties that make water biologically important are molecular polarity, thermal stability (

Water loss during air breathing, Normal 0 false false false...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Why does thermal inversion increases air pollution, Why does thermal invers...

Why does thermal inversion increases air pollution? What harm can thermal inversion cause to humans? Thermal inversion confines at low altitude a layer of pollutants that would

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