Nuclear membrane - structure of nucleus, Biology

Assignment Help:

KARYOTHECA OR NUCLEAR MEMBRANE

It is also called Nucleolemma, term given by Erclab & Hertwig.
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.
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.
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.
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 .

Related Discussions:- Nuclear membrane - structure of nucleus

Define role of vitamin k in controlling gene expression, Define role of Vit...

Define role of Vitamin K in controlling gene expression? Prithrombin, a protein required for blood clotting is assembled with a large number of glutamic acid residues. In the p

Ecology, why would it be difficult to determine accurate values for the fou...

why would it be difficult to determine accurate values for the four variables in the Lotka-Volterra predator-prey model (a, rprey, m, b) for animals in the real world?

Fundamental structure of a virus, Q. What is the fundamental structure of a...

Q. What is the fundamental structure of a virus? Viruses are constituted of genetic material RNA or DNA covered by a protein capsule also known as a capsid. Some viruses, like

Define the precursor of co-enzymes - functions of riboflavin, Define the Pr...

Define the Precursor of co-enzymes - Functions of riboflavin? The major function of riboflavin is to serve as the precursor of the coenzymes FMN and FAD and of the covalently

What is behavioural neurology, What is Behavioural neurology Behavioura...

What is Behavioural neurology Behavioural neurology contains the study of disorders of mood, personality, intelligence, perception and arousal and is concerned with the structu

Enzymatic mutation detection method, This technique utilizes an enzyme reso...

This technique utilizes an enzyme resolvase, endo vii, cloned from the bacteriophage t4. This enzyme has high specificity to find deletions, insertions, and base substitutions muta

Protein synthesis with dna, Protein Synthesis with DNA The central dogm...

Protein Synthesis with DNA The central dogma of modern biochemistry is totally based on the coded information holded within deoxyribonucleic acid (DNA). Double stranded DNA is

Factors influencing rs content -amylose or amylopectiz ratio, Explain the F...

Explain the Factors Influencing RS Content -Amylose or Amylopectiz ratio? Amylose/Amylopectirz ratio: In general, foods containing high amylose/amylopectin ratio lead to higher

Silent myocardial ischaemia, Q. Silent Myocardial Ischaemia? Ans. ...

Q. Silent Myocardial Ischaemia? Ans. This deals primarily with those who have never had symptoms recognized as being of cardiac origin. Others, who have had recognized myo

Feline calcivirus infection, Feline calcivirus infection This disease i...

Feline calcivirus infection This disease is caused by a virus under the family Caliciviridae. Its symptoms include rhinitis, tracheitis and pneumonia. The animals are lethargi

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages