Zygote - embryogenesis, Biology

Assignment Help:

Zygote - Embryogenesis

The fertilized egg or zygote is situated at the micropylar end/pole of the embryo sac, its basal (micropylar) end is attached to the embryo sac wall and apical (chalazal) part projects into the central cell. The zygote usually undergoes a period of rest during which it shrinks. This resting period of the zygote varies with different species and is to some extent dependent on environmental conditions e.g. in Theobroma cacao the zygote divides 14 to 15 days after fertilization, in Oryza saliva zygote divides about 6 hours after fertilization.

A complete cell wall is formed around the zygote. (You would dl that the egg has only plasmalemma and no wall at its apical part). A TEM picture shows that zygote cytoplasm show a more polarized appearance and that is the two poles appear different, micropylar part is vacuolate and chalazal part with a prominent nucleus.


Related Discussions:- Zygote - embryogenesis

Illustrate the horizons in detail, Illustrate the Horizons in detail 'O...

Illustrate the Horizons in detail 'O'  is the  organic horizon  formed from t he organic litter derived from plants and animals and fresh or partially decomposed organic materi

What is an operon, What is an operon, and in what type of organism are oper...

What is an operon, and in what type of organism are operons found? An operon is a series of genes that code for exact products and the regulatory elements that control those ge

Explain the bioavailability of folate, Explain the Bioavailability of Folat...

Explain the Bioavailability of Folate? Bioavailability of folate from naturally occurring food sources is variable and frequently incomplete, as mentioned earlier in the food

What is yellow fever, Q. What is yellow fever? The Yellow fever is a vi...

Q. What is yellow fever? The Yellow fever is a viral infection that occurs mainly in Central Africa and in the Amazon region of South America. It is prevented by vaccination an

Explain gum tragacanth, Gum Tragacanth  Gum tragacanth, the exudation o...

Gum Tragacanth  Gum tragacanth, the exudation of Astragalus species, is defined as the "dried gummy exudate" obtained from Astragalus gummifer Labillardiere. Gum tragacanth is

Metazoans., explain the different types of symmetry in metazoans.

explain the different types of symmetry in metazoans.

Pathogenic bacteria, Pathogenic bacteria Heterotrophic bacteria could ...

Pathogenic bacteria Heterotrophic bacteria could be divided into saprophytes and parasites. Saprophytes normally do not cause any disease and they survive on dead or decaying

Global Warming Prevention, Preventive steps for global warming :  Growing ...

Preventive steps for global warming :  Growing trees in vacant places. Growing social forests and protect them. Promoting abundant growth of phytoplankton plant species in marine

Esophageal obstruction, E s o pha g e a l obstruction It is also...

E s o pha g e a l obstruction It is also known as choke. It may be acute or chronic and is characterized by inability to swallow, regurgitation and bloat. E t

Adaptations in skeleton for upright posture, ADA PTATIONS IN SKELETON FOR ...

ADA PTATIONS IN SKELETON FOR UPRIGHT POSTURE - 1.      Foramen magnum is directed downward so that the head may rest vertically on the vertebral column. 2.      Four curves

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