Nuclear membrane - structure of nucleus, Biology

Assignment Help:

KARYOTHECA OR NUCLEAR MEMBRANE

  1. It is also called Nucleolemma, term given by Erclab & Hertwig.
  2. Karyotheca composed of two unit membranes separated by a 150-300 A° wide perinuclear space. Outer membrame may have 80s ribosomes.E.R. is connected to outer nuclear membrane at several places.
  3. Just beneath inner nuclear membrane, there is a fibrous layer called fibrous lamina. It provides strength to nuclear membrane and also provides attachment site to peripheral heterochromatin.
  4. Nuclear membrane is perforated by nuclear pores of 400 - 1000 Aº diameter with space 1500 Aº . In the oocyte of frog (Xenopus laevis) 30 million nuclear pores are present. Nuclear pores are covered by an octagonal structure composed of eight granular subunits called Annulus or Bleb. Anulus and nuclear pore collectively called pore complex.
  5. These pores regulates transport bet. nucleoplasm and cytoplasm, Small ions like K+, Na+ and Cl- move through nuclear membrane while t-RNA ,r-RNA and m- RNA pass through nuclear pores. Protein nucleoplasmin which occur in pore complex regulates the nucleo cytoplasmic traffic .

357_nucleus.png


Related Discussions:- Nuclear membrane - structure of nucleus

Define the concept of food security, Define the Understanding the Concept o...

Define the Understanding the Concept of Food Security? Food security may be defined as a physical and economic access by all people, at all times, to sufficient food to meet th

Population distribution, Population Distribution - Population Parameters an...

Population Distribution - Population Parameters and Regulation Dispersion or distribution refers to the pattern of distribution of individuals of a population. As shown in Fig

Define carcinogenic - non-dietary factors, Define Carcinogenic - Non-dietar...

Define Carcinogenic - Non-dietary Factors? A large number of agents cause genetic damage and induce neoplastic transformation of cells, they fall into the following categories.

Human skeleton, HUMAN SKELETON - Hard supportive or protective elements...

HUMAN SKELETON - Hard supportive or protective elements of the animal body form the skeleton system. It's study in osteology. EXOSKELETO N - Present outside skin. It

What is a ph meter, What is a pH meter? A pH meter is a device used for...

What is a pH meter? A pH meter is a device used for measuring. pH of any unknown solution. It is composed of: a) A reference electrode b) Glass electrode whose potential

Forestry, Forestry : It concerned with protection or development of forest ...

Forestry : It concerned with protection or development of forest and to explore the outcome or economic potential of forest. Forestry is the art or science of tree resources, inclu

Why is sub-culturing essential in plant tissue culture, Why is sub-culturin...

Why is sub-culturing essential in plant tissue culture? Explain the process of heterosis. How is it dissimilar from inbreeding depression? Where and how is urea produced in

What is the role of stomach in human body, What is the role of Stomach in h...

What is the role of Stomach in human body? The stomach serves both to digest food and to hold it so that it can be gradually released into the small intestine. Food stays in th

Explain the function of the right ventricle, Q. What is the function of the...

Q. What is the function of the right ventricle? To where does the right ventricle pump the venous blood? The venous blood is carried as of the right ventricle to the lungs by t

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

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