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

Explain starch - tests for presence of exoenzymatic activity, Explain Starc...

Explain Starch - Tests for the Presence of Exoenzymatic Activity? Starch is a polymer of glucose linked together by glycosidic bonds. Microorganisms produce hydrolytic enzyme a

Osmotic and ionic regulation, Osmotic and Ionic Regulation The  ammono...

Osmotic and Ionic Regulation The  ammonotelism, ureotelism and uricotelism are the adaptations of the animals for the removal of toxic nitrogenous wastes and thereby maintain

Explain what is fungi, Explain what is Fungi? The fungi are spore-beari...

Explain what is Fungi? The fungi are spore-bearing eukaryotic organisms without chlorophyll and having absorptive nutrition. These reproduce sexually as well asexually. Primari

What do you understand by serial homology, What do you understand by Serial...

What do you understand by Serial homology? Metamerization results in a linear series of segments which share a common embryonic origin. Ancestrally, all metameres were identica

Explain the anatomic variability of long buccal nerve, Anatomic variability...

Anatomic variability of long buccal nerve demands caution during surgery. Discuss Long buccal nerve, a branch of the mandibular division of trigeminal nerve emerges deep to the

What is oxytocin receptors, Which of the following serves as an actuating s...

Which of the following serves as an actuating signal, or as part of an actuating signal, in a positive feedback system? A. Blood plasma levels of PTH (Parathryroid Hormone).

Weight of plants - quantitative characters, Weight of Plants - Quantitative...

Weight of Plants - Quantitative Characters Weight is one of the most important quantitative characteristics of plants. Quantitatively growth is best measured on the basis of d

Drugs and insulin used in diabetes, Q. Drugs and Insulin used in diabetes? ...

Q. Drugs and Insulin used in diabetes? When diet, exercise or even weight reduction do not improve the diabetic symptoms and blood sugar levels, the uses of hypoglycemia drugs

What is the importance of pantothenic acid, What is the Importance of panto...

What is the Importance of pantothenic acid One of the active forms of pantothenic acid is coenzyme A, which is involved in numerous metabolic functions. It is involved in t

What is the process of breathing, What is the process of Breathing? Oxy...

What is the process of Breathing? Oxygen is supplied to the blood, and carbon dioxide is removed from the blood by the process known as breathing. Air is moved into an exchan

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