Nuclear membrane - structure of nucleus, Biology

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

Posted Date: 10/5/2012 7:57:48 AM | Location : United States







Related Discussions:- Nuclear membrane - structure of nucleus, Assignment Help, Ask Question on Nuclear membrane - structure of nucleus, Get Answer, Expert's Help, Nuclear membrane - structure of nucleus Discussions

Write discussion on Nuclear membrane - structure of nucleus
Your posts are moderated
Related Questions
Neuropsychological assessmnet of older children In the recent years, the field of child neuropsychology has undergone tremendous growth. There has been a burgeoning interest in

Illustrate about the Principle of Context A third principle guiding the neuropsychological assessment of children is that environment contexts help to constraint and determine

what is amniocentosis

Qualitative Changes The qualitative changes in the structure of proteins in response to stress can lead to the following: Resistance against denaturation of prote

What are the similarities between chlorplasts and prokaryotic cells?

What is Cyanobacteria or Blue-green bacteria? Blue-green bacteria, or cyanobacteria, used to be classified as blue-green algae within the Plant Kingdom, primarily because they

Advances in neurodiagnostic techniques Major scientific and technology advances have made it easier to correlate behaviours suspected as having a neurological basis with actual

Mechanisms for Response – Protozoan Protozoa are sensitive to many kinds of stimuli like touch, temperature changes, light, chemicals, etc. It is not clear how they do so but

Most forms of cardiac diseases, like hypertension, valvular diseases and coronary artery diseases manifest as low output heart failure. Systemic vasoconstriction with cold extremit

What is Invertebrates? Invertebrates: About 99% of all the animals lack backbones, and are invertebrates! Invertebrates include the phylum Arthropoda, or the animals with joi