If stem cells divide equally, so both daughter cells look more or less the same, each one becomes another stem cell. If the split is unequal, neurons form prematurely. Sam Kean celldaughterdivide Change image and share on social
Every glass thermometer has subtle variations in the size and shape of the bulb at the bottom and the capillary tube inside, as well as variations in the width of gradations on the side. The compounded effect of these uncertainties is that each thermometer reads temperature slightly differently. Sam Kean bottombulbcapillary share on social
The hippocampus helps record both types of memories initially, and it helps retain them for the medium term. The hippocampus also helps us access old personal memories in long-term storage in other parts of the brain. Sam Kean accessbrainhelp share on social
Geneticists in the early 1900s believed that nature - in an effort to avoid wasting precious space within chromosomes - would pack as many genes into each chromosome as possible. Sam Kean 1900savoidbelieve Change image and share on social
Among physicists and chemists, cold fusion - nuclear fusion at close to room temperature - enjoys a reputation about on par with creationism. Sam Kean chemistclosecold Change image and share on social
In a vague way, I always knew neurosurgery was different - more delicate, more difficult, more demanding. After all, we say things like, 'I'm no brain surgeon,' for a reason. Sam Kean braindelicatedemand Change image and share on social
Animal vision - including human vision - is so biased toward movement that we don't technically see stationary objects at all. Sam Kean animalbiashuman Change image and share on social
Most stars just fuse hydrogen into helium, but larger stars can fuse helium into other elements. Still larger stars, in turn, fuse those elements into slightly bigger ones, and so on. Sam Kean bigelementfuse Change image and share on social
In 'The Violinist's Thumb,' I talk about the poignancy of cells leaking across the placenta into both the mother and the child. Sam Kean cellchildleak Change image and share on social
The more that I looked at DNA, the more I realized it was nature and nurture. It's how genes and your environment work together to produce the person you are. Sam Kean dnaenvironmentgene Change image and share on social