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

Pets, Pets, Medical Research and Zoos - Wildlife Animals and plants ar...

Pets, Medical Research and Zoos - Wildlife Animals and plants are gathered throughout the world for zoos, private collectors, pet shops and researchers in biology and medicine

Infectious bursal disease, I nfe c tio u s bursal disease Infectio...

I nfe c tio u s bursal disease Infectious bursal disease (popularly known as Gumboro disease) is an acute contagious disease of young chicks caused by an RNA virus, a memb

Describe the common operations performed in pcs, Describe the common operat...

Describe the common operations performed in paediatric cardiac surgery 1) Closed Heart Surgery: Surgery on Heart or Great Vessels done without using the Heart-Lung machine.

Explain the requirements of special stains, Explain the requirements of Spe...

Explain the requirements of Special Stains? Special stains are required to make spores clearly visible. Different techniques like negative staining, dorner staining method, sch

How is the nervous system of molluscs organized, Q. How is the nervous syst...

Q. How is the nervous system of molluscs organized? Molluscs have well-developed sensory structures. It is accepted that cephalopods, like squid and octopus, have eyes with ima

Bronchial asthma, Bronchial asthma: Bronchial asthma is characterised ...

Bronchial asthma: Bronchial asthma is characterised by bouts of  dyspnoea as a result of  temporary narrowing of bronchi due to bronchial spasm, mucosal edema and thick secret

Genetic explanation for the appearance, You work with flies and you have id...

You work with flies and you have identified a single gene that can cause flies to either have two heads or one head (depending on the genotype of this gene), and that is all you kn

How can the endoskeleton of echinoderm, Q How can the endoskeleton of echin...

Q How can the endoskeleton of echinoderms be characterized in comparison to analogous structures present in vertebrates, arthropods and molluscs? The echinoderm skeleton is int

Calculate the molar concentration of illinic acid, Calculate the molar conc...

Calculate the molar concentration of illinic acid and of its conjugate base illinate ion (in moles/L; M) in a 0.002 M illinate buffer at pH 12.0. The pKa of illinic acid is 6.7. En

Can you illutrate autoimmune diseases, Q. What is the name given to conditi...

Q. What is the name given to conditions in which the own immune system of the individual is the agent of diseases? What are some examples of these conditions? Diseases caused b

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