Question

Nuclear pore consists of

• A. Annulus
• B. Neuropore
• C. Deuropore
• D. None of the above

Answer 1

The correct option is A Annulus

In eukaryotic organisms, the nucleus has five parts - Nuclear envelope, Nucleoplasm, Nuclear matrix, Chromatin and Nucleolus. The Nuclear Envelope is also called as Karyotheca. It is made up of two membranes separated by 10 to 70 nm of Perinuclear Space. The outer membrane may have ribosomes and interconnections with ER. Nuclear envelope has a large number of pores with a diameter of 200 to 800 angstroms. Sections through the nuclear pores show the presence of an electron dense ring or cylinder within the pore. This electron dense material has been called the Annulus. The actual opening of the nuclear pore is thus confined to the cavity of the annulus. The annulus extends both into the cytoplasm and the nucleoplasm.

So, the correct answer is 'Annulus'