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

Determine the testing for albumin in urine, Determine the Testing for Album...

Determine the Testing for Albumin in Urine Acetic Acid Test About 2 - 8 mgm/dl of protein is excreted in urine which is not usually detected by routine test. The testing o

Which hormone influence maturation of the ovarian follicles, Q. After mense...

Q. After menses what is the hormone that influences the maturation of the ovarian follicles? The maturation of the ovarian follicles after menses is stimulated by the action of

Define fish as a rich source of protein, Define Fish as a rich source of pr...

Define Fish as a rich source of protein? The edible portion is skeletal muscles of the body. Even though the skeletal muscles of different animals are basically similar, fish s

The transport system in earthworm., The transport system in earthworm ...

The transport system in earthworm The scientific name of earthworm is megascolex. It consists of hearts, blood vessel and blood. There are 8 pairs of hearts in the earthw

List principles to keep in mind for designing the messages, Q. List princip...

Q. List principles to keep in mind for designing the messages? o Develop a positive theme. Approaches are more effective when they promote positive messages that state clear

Explain tetralogy of fallot repair and transposition, Explain Tetralogy of ...

Explain Tetralogy of fallot repair and Transposition of arteries? Tetralogy of Fallot Repair: This involves RV outflow resection, closure of the VSD and enlargement of the RV

State structural abnormality and unique behavioural, State the term - struc...

State the term - structural abnormality and unique behavioural The link between structural abnormality and unique behavioural aberration has become clearer as technological adv

Technique-ross operation--surgical techniques, Technique : The suitability...

Technique : The suitability of the pulmonary autograft for aortic valve replacement has to be studied by accurate measurement by echocardiogram of the aortic and pulmonary annuli.

Alcohol consumption by diabetes patient, Q. Alcohol consumption by diabetes...

Q. Alcohol consumption by diabetes patient? Intake of alcohol should be limited. It is high in calories, lacks essential nutrients and may therefore promote ketoacidosis, hyper

Explain about blood pressure, Explain about Blood pressure Blood press...

Explain about Blood pressure Blood pressure is explained as the force exerted by the blood against the walls of the arteries. Blood pressure (BP) can be described as the fo

Write Your Message!

Name

Email id

Message

Verfication Code

User Account

All Pages