Types of ovules, Biology

Assignment Help:

Types of Ovules

Anatropous

This is the most common type of ovule in angiosperms in which the ovule undergoes curvature such that the micropylar end comes to lie parallel to the funiculus.

Orthotropous

In this type of ovule no curvature occurs and the micropyle lies in a straight line with respect to the funiculus.

Hemi anatropous

The hemi anatropous condition results from the curvature of the ovule such that the micropyle comes to lie at right angles to the funiculus.

Campylotropous

In campylotropous type, the ovule is curved but the curvature is less than that in the anatropous condition.

Amphitropous

The amphitropous ovule looks like the campylotropous ovule at the first glance. But there is a point of distinction. In this type the nucellus and the embryo sac are curved like a horse shoe.

Circinotropous

Besides the above basic forms, another interesting type that you should know is the circinotropous ovule. In the early developmental stages of such ovules the .nucellar protuberance is more or less in line with the axis. In the further developmental stages, due to unilateral growth, it assumes anatropous form. The curvature does not stop at this, but continues until the ovule has turned over completely so that the micropylar end again points upwards. This kind of ovule is common in families Cactaceae and Plumbaginaceae.


Related Discussions:- Types of ovules

Congenital defects related to kidney/upper urinary tract, Congenital Defect...

Congenital Defects Related to Kidney/Upper Urinary Tract i) Renal Agenesis  A new born baby with this condition may show low set ears, flat nose, prominent epicanthic

Explain the treats bacterial infections, Is a viral infection treated with ...

Is a viral infection treated with the same kind of drug that treats bacterial infections? Antibacterial drugs, potent against a great variety of bacteria, are not effective aga

How arab influence on the development of anatomy, Please on 3 separate para...

Please on 3 separate paragraph a. Examine the contributions of select scientists from the Greek and Roman period. b. Explore the Arab influence on the development of anatomy

What is the indication of chronic pulmonary thromboembolism, Chronic Pulmon...

Chronic Pulmonary Thromboembolism :  The operation recommended is pulmonary thrombo endarterectomy. Indication :  The main indication for surgery is when patients with chroni

Describe female and male surgical sterilization, Q. What are the most commo...

Q. What are the most common methods of female and male surgical sterilization? Vasectomy is the majority common method of surgical sterilization in men in vasectomy the vas def

Ecretory system, excretory product of marine teleost

excretory product of marine teleost

Significance of apomixis, Significance of Apomixis Apomixis offers th...

Significance of Apomixis Apomixis offers the possibility of indefinite multiplication of especially favorable biotypes without any variation due to segregation or recombinati

How does the male gamete penetrate the egg cell, How does the male gamete p...

How does the male gamete penetrate the egg cell? How does the female gamete protect itself from the entrance of more gametes after the entrance of the first sperm cell? The spe

Observing root hairs, Observing root hairs Study the root hairs with a ...

Observing root hairs Study the root hairs with a hand lens and view how they are constructed.

Human biology , Your final assignment is to write an (~2000 words) on any d...

Your final assignment is to write an (~2000 words) on any drug that is currently approved by the FDA, describing how the drug works based on the mechanisms of human biology describ

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