The loci that encode hemoglobins are members of a gene family, which is a set of loci that arose by duplication.

TLS Online TPP Program

#Id: 7775

#Unit 2. Cellular Organization

The total mass of the pore structure is 60,000– 80,000 kDa in vertebrates, which is about 16 times larger than a ribosome.

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#Id: 7776

#Unit 2. Cellular Organization

In one minute, each NPC is estimated to import 60,000 protein molecules into the nucleus, while exporting 50–250 mRNA molecules, 10–20 ribosomal subunits, & 1000 tRNAs out of the nucleus.

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#Unit 2. Cellular Organization

An NPC is made up of many copies of some 30 different proteins called nucleoporins.

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#Id: 7778

#Unit 2. Cellular Organization

Eight approximately 100-nm long filaments extend into the nucleoplasm with the distal ends of these filaments joined by a terminal ring, forming a structure called the nuclear basket.

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#Id: 7779

#Unit 2. Cellular Organization

The nucleoporins are of three types: 

a. Structural nucleoporins

b. Membrane nucleoporins

c. FG-nucleoporins

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#Id: 7780

#Unit 2. Cellular Organization

A set of seven structural nucleoporins forms a Y-shaped structure about the size of the ribosome, known as the Y complex.