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

Differences between genomes in prokaryotes and eukaryotes, What are the dif...

What are the differences between genomes in prokaryotes vs. eukaryotes?

Can you explain tannins, Q. Can you explain Tannins? Tannins are anoth...

Q. Can you explain Tannins? Tannins are another class of compounds which interfere with the absorption of minerals like iron and reduce the availability of proteins by bindin

Joint, Ask question #Minimum 100 words what is joint accepted#

Ask question #Minimum 100 words what is joint accepted#

Factors affecting normal blood sugar levels, Q. Factors Affecting Normal Bl...

Q. Factors Affecting Normal Blood Sugar Levels? Earlier in our discussion, we learnt that insulin is the most important factor responsible for normal blood sugar levels. Now we

Pathogenesis, The interactions between the human host and selected microorg...

The interactions between the human host and selected microorganisms that culminate in IE involve the vascular endothelium, hemostatic mechanisms, the host immune system, gross anat

Etiological factor of dyspepsia, Q. Etiological factor of dyspepsia? Th...

Q. Etiological factor of dyspepsia? The main etiological factor of dyspepsia is the failure of proper digestion and absorption of food in the alimentary tract and the consequen

Define vitamins requirement to avoid underweight problem, Define Vitamins r...

Define Vitamins requirement to avoid underweight problem? Vitamins and Minerals: If the diet provides good amounts of fresh fruits and vegetables, vitamin or mineral supplement

Define systematic botany - taxonomy, Define Systematic Botany - Taxonomy? ...

Define Systematic Botany - Taxonomy? We will now learn something mare about systematic botany. The early recognition of harmful and useful plants was the beginning of systemati

Hepatitis, He p atitis Hepatitis is defined as degenerative/ inflamma...

He p atitis Hepatitis is defined as degenerative/ inflammatory processes of the liver. The clinical manifestations associated with hepatic dysfunctions results from impairmen

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