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 do you mean by congenital long qt syndrome, Q. What do you mean by Con...

Q. What do you mean by Congenital Long QT Syndrome? There is a rare group of young patients who suddenly pass out due to a spontaneous ventricular tachycardia and often have fa

Food web - ecosystem, Food Web - Ecosystem A plant may serve as a food...

Food Web - Ecosystem A plant may serve as a food source for many herbivores simultaneously, e.g. grass plants can support deer, cow, grasshopper or rabbit. Similarly a herbivo

Physiology, what happens to your total peripheral resistance when you go fr...

what happens to your total peripheral resistance when you go from a warm room to cool outside air

Care of psychoemotional aspects of patient in icu, Care of Psychoemotional ...

Care of Psychoemotional Aspects ICU area is an area which is cut off from outside world. Modem ICUs are built in such a way that the sensory deprivation is reduced. Ta

What are the advantages of yoga, What are the advantages of Yoga Yoga h...

What are the advantages of Yoga Yoga has been derived from the Sanskrit word Yuj which means union. It is popular since ancient times. It is also one of the means to maintain f

Define body mass index (bmi) or quetelet index, Define Body Mass Index (BMI...

Define Body Mass Index (BMI) or Quetelet Index? BMI is an index measure of body fat used for the assessment of disease risk.  It is a figure which gives an indication of weight

What is heterophagic intracellular digestion, Heterophagic intracellular di...

Heterophagic intracellular digestion is the breaking into minute substances of external substances engulfed in the cell by pinocytosis or phagocytosis. Phagosomes or pinosomes fuse

Define hydroxybenzoic acid and hydroxycinnamic acid, Define Hydroxybenzoic ...

Define Hydroxybenzoic acid and Hydroxycinnamic acid? Hydroxybenzoic acid: e.g. ellagic and gallic acids, which are hydrolyzable tannins, present in berries and nuts. Hydroxy

Respiratory organ in animals, RESPIR A T ORY ORGANS IN ANIMALS - ...

RESPIR A T ORY ORGANS IN ANIMALS - In Protozoa plasmalemma functions as respiratory surface. In Porifera, respiration occur through body wall. In Coelentrata resp

What are the cells that form the cartilaginous tissue, Q. What are the cell...

Q. What are the cells that form the cartilaginous tissue? The main cells of the cartilages are the chondrocytes originated from the chondroblasts that secrete the intersticial

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