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

What are the kinds of plant geotropisms, What are the kinds of plant geotro...

What are the kinds of plant geotropisms? Why do the root and the stem present opposite geotropisms? The kinds of geotropisms are the positive geotropism, that in which the plan

Impediments to infuse biology - lack of trained people, Define Impediments ...

Define Impediments to infuse biology - Lack of trained people? At present, biologists as a rule have not been trained sufficiently in quantitative approaches. A heavy dose of m

Principal sources of excessive nitrate and phosphate, What are the principa...

What are the principal sources of excessive nitrate and phosphate in rivers and lakes? Excessive nitrates and phosphates come majorly from sewage effluents and intensive agric

Difference between alpha glucose and beta glucose, What is the difference b...

What is the difference between alpha glucose and beta glucose? Why are they different?

Define the enzyme deficiency or defects, Define the Enzyme deficiency or de...

Define the Enzyme deficiency or defects? A food sensitivity or intolerance can occur when the body has difficulty in digesting a particular food and therefore reacts against it

Injury to adrenal cortex, Injury to adrenal cortex is not likely to affect ...

Injury to adrenal cortex is not likely to affect the secretion of which one of the following? 1. Aldosterone 2. Both Androstenedione and Dehydroepiandrosterone 3. Adrenali

What are genotypes and phenotypes, The agouti locus in mice has three allel...

The agouti locus in mice has three alleles: A is recessive and confers a black coat, A is dominant to a and confers an agouti coat, and AY is dominant to both and confers a yellow

Digestive system, describe the effects of the failure of the pancreas to pr...

describe the effects of the failure of the pancreas to produce sufficient insulin

#to work as expert, Ask question #process for work as expert#

Ask question #process for work as expert#

Chest drainage tubes (24-72 hours), Chest Drainage Tubes (24-72 hours) ...

Chest Drainage Tubes (24-72 hours) Continue milking of chest tube hourly.  Monitor the amount, colour and record on the flow chart.  Assess dressing for any soak

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