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

What is streatorrhoea, Q. What is Streatorrhoea? Streatorrhoea is more ...

Q. What is Streatorrhoea? Streatorrhoea is more common in Crohn's disease due to heal resection. This may favour calcium-fatty acid complex formation and increased excretion. I

Show the ph range of natural honey, Q. Show the pH range of natural honey? ...

Q. Show the pH range of natural honey? The pH of natural honey ranges from 3.4 to 6.1. Acidity of honey is primarily due to presence of acids such as gluconic acid, pyruvic a

Discuss in detail about the mitochondria, Discuss in detail about the Mitoc...

Discuss in detail about the Mitochondria An important function of the cell is to derive energy from the different oxidisable nutrients, such as, carbohydrates and fats supplied

Define comprehensive dietary management regime of patient, Define Comprehen...

Define Comprehensive Dietary Management Regime of Patient? A comprehensive dietary management regime of the patient should be based on the patient profile as gathered pre and p

Does natural selection produce an effect directly on genes, Does natural se...

Does natural selection produce an effect directly on genes, on genotypes, or on phenotypes? Explain please.

What is histone methyl transferases, Histone methyl transferases (HMTs) hav...

Histone methyl transferases (HMTs) having a protein domain called SET. This domain is responsible to adding methyl groups to histones. Which of the following is a false statement r

Determinants of health status, Determinants of Health Status The linkage...

Determinants of Health Status The linkage between economic development and health was discussed in the previous unit. The present unit deals with an identification of the factor

Why is blood important for larger animals, Q What is the alternative means ...

Q What is the alternative means for transport of substances in animals without a circulatory system? Why is blood important for larger animals? In animals that don't present th

What is the mendels first law, What is the Mendel's first law? The Mend...

What is the Mendel's first law? The Mendel's first law postulates that a characteristic (trait) of an individual is always verified by two factors, one inherited from the fathe

State about endocrine system, Endocrine System In endocrine system duct...

Endocrine System In endocrine system ductless gland or specialized cells release chemicals called hormones into the circulating blood. These hormones influence the functions of

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