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

Preference share capital or quasi-equity, Preference Share Capital or Quasi...

Preference Share Capital or Quasi-Equity It is also called quasi-equity because it combines features of equity and those of debt.  It is preference because it is preferred to

Define about the paper chromatography, Define about the Paper Chromatograph...

Define about the Paper Chromatography? Paper chromatography is a very useful technique for separating mixtures of metal ions, anions, amino acids, sugars, dyes, drugs, etc. The

Sickle cell, Sickle cell anaemia in man is caused by a defective chain of h...

Sickle cell anaemia in man is caused by a defective chain of haemoglobin. The abnormal haemoglobin known as MbS differs from natural haemoglobin (HhA) in one amino acid. A substitu

Illustrate hypertrophic cardiomyopathy?, Q. Illustrate Hypertrophic cardiom...

Q. Illustrate Hypertrophic cardiomyopathy? It is a genetic disorder due to mutations in the gene that encodes for β-Cardiac myosin heavy chain (Localised to chromosome 14). It

What is the type of circulatory system present in arthropods, What is the t...

What is the type of circulatory system present in arthropods? Do these animals have heart and respiratory pigments? In arthropods the respiratory system is open (lacunar). Blo

Determine what is dermal branchiae, Determine what is dermal branchiae? ...

Determine what is dermal branchiae? External extensions of outer epidermis and peritoneum of the echinoderm body cavity. Both outer epidermis and inner peritoneum are lined wit

What are the ploidies of the new cells, In which meiotic division does the ...

In which meiotic division does the separation of identical chromatids occur? After the end of this process what are the ploidies of the new cells? The separation of identical c

Excretory organ and waste product, name the excretory ogran and waste produ...

name the excretory ogran and waste product formed in various types of animals

Obelia, Economic importance of obelia

Economic importance of obelia

Illustrate about the complex partial seizures, State about the Complex part...

State about the Complex partial seizures Complex partial seizures, another type of focal seizure, originate most commonly in the temporal lobe. Complex partial seizures are cha

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