Size: 2753
Comment:
|
Size: 2753
Comment:
|
No differences found! |
The Body
A Guide for Occupants
Bill Bryson 2019 Bvt Lib 612 BRY
Notes and bibliography and index, yay!
CH01 How to Build a Human
001-004 silliness about the cost of the elements in your body ... actually the cost of purifying those elements. That can be turned upside down; there are 10 tonnes of CO2 carbon above my 0.7 acres, and another 30 tonnes (est) of carbon in my trees and bushes and grass. A few more tonnes in the wood of my house, and the books on my shelf, call that 10 tonnes, for a total of 50 tonnes for a "home price" of perhaps $500K; $10/kg carbon. For the rest of the elements, dig down, there is plenty of everything, arguably $4.7 trillion dollars worth of elements and compounds.
The reference human is Benedict Cumberbatch, 78 kg, ( 18.5% carbon by weight hence 15 kg, so the limiting element of human existence (carbon) cost of a my-backyard-sourced Cumberbatch is $150. Using a less expensive carbon source (like coal, closing at $340/ton (907 kg) is $0.40 per kilogram, or about $6 per Cumberbatch. Humans add 40 billion tonnes of CO2 to the atmosphere per year, perhaps 11 billion tonnes of carbon, or about one million "carbon-Cumberbatchs" per second.
Personally, I believe one Cumberbatch is ample, and would prefer the atmospheric excess turns into 3000 big trees per second. As I write this, way too many Oregon trees are burning into CO2 instead.
- 007 DNA All Humans share 99.9 percent of their DNA (3 billion base pairs) typical differences 3 million base pairs, 100 unique mutations
- 009 37 trillion cells
CH02 skin and hair
- 011 Two square meters, 4 to 7 kg
- 012 live inner layer dermis, outer layer epidermis, outermost layer stratum corneum, dead cells replaced every month
- one million flakes (squamae) per hour
- 2M to 5M follicles, 4 to 10M sweat glands
- 013 Meissner's corpuscles sense light touch, Ruffini corpuscles sense HOT, Merkel cells pressure, Pacinian corpuscles vibration 10nm
- 014 Race/skin color is a millimeter layer of epidermis, pigmentation is more than 120 genes
- 015 all have same number of melanocytes, more melanin produced for some
- 016 lighter skin increases vitamin D synthesis
- 019 hairlessness 1.2 to 1.7 MYA
- 020
CH03 microbes
CH04 brain
CH05 head
CH06 mouth and throat
CH07 heart and blood
CH08 body chemistry
CH09 skeleton
CH10 bipedalism
CH11 equilibrium
CH12 Immune system
CH13 Lungs
CH14 Food
CH15 Guts
CH16 Sleep
CH17 Sex
CH18 Pregnancy
CH19 Pain
CH20 Diseases
CH21 Cancer
CH22 Medicine
CH23 Death