I don't understand the question

[yousuf89]

which human cells do not have entire DNA sequence genome to produce every protein type?

 

I don't really understand what the question wants , does it mean which cells doesn't have a nucleus or something......

[ewmon]

There's at least a couple of answers, but I think I know the specific answer hinted at here. This question is a little tricky, so don’t take it personally.

 

Think of some of the basic things that can happen with DNA, and think of what is a (hopefully) obvious way that only part of the DNA is present. Also relax your typical definition of a human “cell” -- partial DNA is obviously an odd situation, so think “specialized”.

 

You can ignore the “to produce every protein type” part of this puzzle because this is an obvious result if part of the DNA is missing. If what I’m thinking is right, I hope there's some interesting follow-on discussion about "not every protein".

[pioneer]

For the most part, all the cells in the human body have the same DNA. The DNA in each cell type is differentiated, via packing proteins, causing each cell type to have access to a specific fraction of the total DNA. Conceptually, one can turn any cell, into any cell, since they all have the same DNA.

 

During cell cycles, the DNA of all the differentiated cell types form the same chromosomes. All the daughter cells, of all the differentiated cell types, start with the exact same DNA packing configuration, yet each is able to revert this to the specific distribution. There is one observation that explains this in the simplest terms.

 

Red blood cells lose their entire DNA, but continue to function. This shows that the protein grid is quite self sufficient. During cell cycles, when the DNA is totally taken off-line for duplication and/or packed away as chromosomes, the protein grid continues the cellular business in autonomous fashion. I would assume the specific protein grid, connected to a cell type, has the duty of unpacking the DNA into the specific shape that will be in equilibrium with the grid's protein capacitance.

[yousuf89]

Are u saying that red blood cell is one of the human cell that do not have entire DNA sequence genome to produce every protein type

 

For the most part, all the cells in the human body have the same DNA. The DNA in each cell type is differentiated, via packing proteins, causing each cell type to have access to a specific fraction of the total DNA. Conceptually, one can turn any cell, into any cell, since they all have the same DNA.

 

During cell cycles, the DNA of all the differentiated cell types form the same chromosomes. All the daughter cells, of all the differentiated cell types, start with the exact same DNA packing configuration, yet each is able to revert this to the specific distribution. There is one observation that explains this in the simplest terms.

 

Red blood cells lose their entire DNA, but continue to function. This shows that the protein grid is quite self sufficient. During cell cycles, when the DNA is totally taken off-line for duplication and/or packed away as chromosomes, the protein grid continues the cellular business in autonomous fashion. I would assume the specific protein grid, connected to a cell type, has the duty of unpacking the DNA into the specific shape that will be in equilibrium with the grid's protein capacitance.

[ewmon]

This sounds like a homework question, and I won't give you the answer, just help you to think toward it.

 

Red blood cells is one answer, and you can use this if you want, but it may not be the answer the teacher/prof wants.

 

Think extreme "specialization". Your teacher/prof has probably taught you the answer already, you just haven't thought about it before in this way. It's one of these "Oh yeah!" answers.

Edited April 4, 2010 by ewmon

[DctrZaius]

Yes red blood cells don't have a nucleus but the first type of cells that sprung to mind was B and T cells. They undergo irreversible DNA arrangements in order to produce diversity in their receptors.

[The Foot Tapper]

The answer will most likely be erythrocyte, or something similar.

[ewmon]

Gametes carry half the genetic information of a normal cell.

 

The interesting follow-on discussion I thought would happen involves how sperm and eggs survive (and do what they do) with only half the normal genetic information.