Re:Japan has 33k businesses at least a century old
by WoahNoun on Friday February 14, 2020 @12:26AM
(#22324171)
You think every brain cell is replaced every few months? Please delete this comment and read a biology textbook.
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Re:Japan has 33k businesses at least a century old
by msiyer on Friday February 14, 2020 @12:57AM
(#22324288)
https://www.ncbi.nlm.nih.gov/pubmed/16495940?access_num=1649...
Adult neurogenesis or brain plasticity is a fact. Skin cells, blood cells and all types of cells have a finite lifespan - a few days to a few months.
Re:Japan has 33k businesses at least a century old
by hn_throwaway_99 on Friday February 14, 2020 @01:10AM
(#22324325)
Just because neurogenesis exists, it most definitely does not follow that "every single cell in the body of a plant or animal is replaced every few months", which is what you said.
Osteocytes in human bone can live up to 50 years.
Re:Japan has 33k businesses at least a century old
by msiyer on Friday February 14, 2020 @01:38AM
(#22324446)
Can live up to 50 years. OK. What happens when they do not? Does the body not regenerate them? Various kinds of stress can cause them to not live that long. It is not as black and white.
Re:Japan has 33k businesses at least a century old
by shreyansj on Friday February 14, 2020 @12:31AM
(#22324187)
Are you saying that a brain cell is immortal through one’s life?
Re:Japan has 33k businesses at least a century old
by ryanhuff on Friday February 14, 2020 @12:51AM
(#22324265)
https://www.nationalgeographic.com/science/phenomena/2013/02...
"New neurons are made in just two parts of the brain—the hippocampus, involved in memory and navigation, and the olfactory bulb, involved in smell (and even then only until 18 months of age). Aside from that, your neurons are as old as you are and will last you for the rest of your life. They don’t divide, and there’s no turnover."