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Fact File - taken from the book "Quest:
The Essence of Humanity" by Charles Pasternak
- Read an article here
by Charles Pasternak
2121/ Molecules are all
extremely small: molecules like water, oxygen or carbon dixide
are less than a billionth of the size of the point of a needle;
carbohydrates like glucose, and fats like cholesterol are
10 times larger; proteins and carbohydrates like starch are
a 100 times larger, and DNA - the biggest molecule of living
matter - is a million times larger (but still only visible
with an electron microscope).
2122/ Living orgasnisms
consist of nothing but molecules. There are some thousand
million million million million (10 to the 27th power) molecules
of water, a hundred thousand million million million (10 to
the power 23) molecules of protein and ten thousand million
million (10 to the 16th power) molecules of DNA in an adult
human being.
2123/ Cells of plants
and animals are of similar size (approximately one hundredth
of a millimetre in diameter, just to small to see with the
naked eye), irrespective of whether they are part of a daisy
or a beetle, a giant sequoia or an elephant.
2124/ The number of cells
in an organism depends on its size: an adult human being contains
some hundred million million (10 to the power 14) cells.
2125/ Any one cells contains
around ten million million (10 to the power 13) molecules
of water, a thousand million (10 to the power 9) molecules
of protein and about a hundred (10 to the power 2) molecules
of DNA.
2126/ Atoms do not exist
as discrete entities (except at very high temperartures).
It is molecules and the reactions between them that make up
the chemistry of life.
2127/ There are 20 different
types of amino acid, and any one can be linked to another.
The length of the chain is variable: some proteins are made
up of relatively short chains, others consist of longer chains.
Insulin is an example of the first type, haemoglobin of the
second. So when a molecule is referred to as being a protein,
that defines merely its composition: lots of amino acids linked
together in a chain.
2128/ In the human body
there are over 100,000 different types of protein, each with
a specific function.
2129/ DNA consists of
atoms of hydrogen, oxygen, carbon, nitrogen and phosphorus,
linked together in even longer chainsthan proteins. again,
the chain consists of smaller units, that in this case arecalled
nucleotides. Just four types of nucleotide make up DNA: adenine
nucleotide (called A for short), cytosine nucleotide (C),
guanine nucleotide (G) and thymine nucleotide (T).
2130/ A molecule of DNA
is millions of times longer than a protein.
2131/ The part of a molecule
of DNA that codes for a single protein is called a gene, and
there are more than 1000 genes arranged end to end, in each
molecule of DNA.
2132/ We owe the concept
of the gene to Gregor Mendel, a Moravian monk, quietly crossing
different strains of sweet pea in a monastery garden at Brunn
(now Brno in the Czech Republic). He carried out the first
scientific experiment on cross-breeding, which man had been
practicing for 10,000 years. He was searching for nothing
less than the mechanism by which certain features are passed
on from one generation to the next. What he found was that
characteristics of the sweet pea plant, like tallness or shortness,
presence or absence of colour in the blossoms, wrinkled or
smooth appearance of its seeds are inherited independently
of each other, in a predictable manner. From this he deduced
that the characteristics are transmitted as separate elements.
He called them genes.
2133/ It has been estimated
that during the last 300 years the rate of extinction of birds
and animals has increased some 5-50-fold over the 'natural'
rate, which is roughly one species every 4 years. Put another
way, the total lifetime of any one species is, on average,
very approximately a million years. Within the last decades
of the twentieth century, the extinction rate rose a further
20-fold. We are now losing roughly one species of animal or
plant every day. One way or another, more than 99.9% of the
species that have ever lived on this planet are extinct.
2134/ The temperature
on Earth drops no more than 30 - 44 degrees centigrade at
best come nightfall, which may be compared with a change of
more than 1000 degrees centigrade between day and night on
the surface of the moon.
2135/ The neocortex is
part of the outer layer of the brain (the cortex) that is
concerned with higher cerebral functions like intellect, memory
and consciousness. In most mammals the neocortex accounts
for 30-40% of total brain volume, but in primates it is higher:
from 50% in prosimians (primitive monkeys) to 80% in humans.
2136/ The real name of
the author we all know as 'George Eliot' is in fact Mary Ann
Evans and 'George Sands' was Amandine-Aurore Lucille Dupin.
2137/ Over 15% of people
throughout the world are illiterate, but the rate is much
higherin certain areas. In rural Pakistan for example, 90%
are illiterate, and there are villages not 100 miles from
bustling Karachi where the illiteracy among 15 year girls
is 99.7%.
2138/ More than 20% of
adults in the UK are defined as functionally illiterate, which
places the UK - together with Ireland - at the bottom of the
literacy league within developed countries.
2139/ During World War
II, the USA was carrying out research and development of anthrax
spores and botalinum toxin for possible use against Germany.
By 1944 it had installed 12 20,000-gallon fermentors at Vigo,
Indiana, capable of producing more than a million 4lb anthrax
bombs a month. Britain alone had ordered an initial shipment
of 500,000 bombs. In the event, none was used.
2140/ Between 1750 anf
1850, when the Industrial Revolution was reaching its peak,
the increase in the population of Western Europe began to
overtake that of India and China: England's population grew
three-fold (from 5.7 million to 16.5 million), whereas that
of China did not quite double (from 215 million to 420 million).
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