Hayflick limit, cell growth, and muscle building questions

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Skhandelwal
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1: Chances are nobody knows if it does.
The article you reference says that clinical studies are required to determine this.

2: Excess nutrients do not necessarily result in cell growth.
What will happen depends on feedback mechanisms in an organism.

3: This has some information on muscles
http://www.nature.com/ncb/press_release/ncb0205.html
 
The cell cycle is an active area of cancer research. Cells also exist in an 'undifferentiated' state, which is when they are actively growing, and a 'differentiated' state, which is when they stop growing and develop functions. People don't know what processes occur in differentiation or how differentiation occurs.

Most live-cell research involves use of cancer cells, as these continue to grow and divide without end. Thus, multiple experiments can be carried out on the same population of cells. They are also clones, but that's another story.

Cells have a preferred size- this has been shown in experiments where cells are confined to smaller and smaller volumes. Too small, the cells die. What the 'volume sensor' is, is not known.

I culture epithelial cells- these cells have a barrier function, and I grow them on permeable supports. The cells have been transfected with "SV40 Large-T antigen" (look that up). My cells grow at the 'permissive' temperature of 33 C and differentiate at 37 C.
 
Skhandelwal said:
http://books.google.com/books?id=_7...0kZpRyE&sig=1S4uUc_dScG6SnQ_ZruPl4Vq3ZU&hl=en

According to that link...cells given poor nutrient grow slowly...animals tested w/ less food ages slowly...lived longer...That is why I thought that excess nutrients makes the cells grow faster...why?
(if you do some more search...you'll find more link by yourself)

There is a distinction here between minimal (or even insufficient nutrients) and excess nutrients. In the first case growth can be restricted due to lack of materials while in the latter growth is tightly restricted by regulatory mechanisms.
 
1. What are regulatory mechanisms?

2. And are you saying that insufficient nutrient can be healthy?

3. If cells don't grow larger, don't apoptosis...then how do they die?
 
You're asking so many questions, and most of them so general, that they are really outside the scope of this forum to answer adequately. Some are so general, you could get your answers from any general biology text (usually within the first few chapters), others you may want to pick up a cell biology text. Get the basic answers from a textbook, and then come back when you can refine your questions to something more specific we could answer without having to re-write a textbook for you.