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

What is micrographia?, Micrographia is abnormally small, cramped handwritin...

Micrographia is abnormally small, cramped handwriting and/or the progression to continually smaller handwriting. This is one of the symptoms of Parkinson''s disease.

What is uric acid , Uric acid is the main nitrogenous waste product o...

Uric acid is the main nitrogenous waste product of uricotelic organisms (birds, insects and reptiles), but is also established in ureotelic organisms from the breakdown of the puri

Consequences of population growth, T he effects of unlimited population gro...

T he effects of unlimited population growth are as follows: 1.         Increase in unemployment. 2.          Low per capita income. 3.         Low living standard

Define myocardial infraction and stress testing, Q. Define Myocardial infra...

Q. Define Myocardial infraction and stress testing? Prediction of disease is one of the primary functions of stress testing. We would like to be able to predict in each patient

Annelids - regeneration in invertebrates, Annelids - Regeneration in Invert...

Annelids - Regeneration in Invertebrates Between the segmented worms both the polychaetes and oligochaetes have remarkable powers of regeneration. Leeches totally lack this ca

Activitiesthat cause fish kills, Explain how human activities can cause an ...

Explain how human activities can cause an imbalance in biogeochemical cycling and lead to problems such as cultural eutrophication and fish kills

Explain various chemical formulas, Explain various chemical formulas? C...

Explain various chemical formulas? Chemical Formulas A molecule can be represented in any of three ways: its chemical formula, structural formula, or Lewis diagram. A chemic

Explain adverse effects of oseltamivir, Explain Adverse Effects of Oseltami...

Explain Adverse Effects of Oseltamivir  Nausea and vomiting can occur. Taking the drug with food decreases the incidence of nausea. In juvenile rats, very high doses of osel

Interior of the left atrium - heart, The left atrium is a thin walled cavit...

The left atrium is a thin walled cavity. Most of the wall is smooth. Musculi pectinati are present only in the auricle of the atrium. The interatrial septum separates the cavity of

Scintillation counter, carnt understand its principle and mode of working

carnt understand its principle and mode of working

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