BBC Science The Theory of (nearly) Everything 2019

(Martin Jones) #1
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ROBERT HOOKE
(1635-1703)
contributed to
fields as diverse
as architecture,
palaeontology and
astronomy. He was
an English researcher,
born on the Isle of
Wight and known for
his difficult manner
and rivalry with
fellow researcher
Isaac Newton.

ANTONIE VAN
LEEUWENHOEK
(1632-1723) was a
Dutch draper and
amateur researcher.
Son of a basket maker,
he was an unlikely
scientist, but his skill
led to him producing
some of the most
advanced microscopes
of his time, and the
discovery of single-
celled organisms.

ALBERT CLAUDE
(1899-1983) moved to
the US in 1929. He was
a Belgian cell biologist
who served for the
British Intelligence
Service during World
War One, and was
rewarded with a
medical education in
Belgium despite not
having the required
qualifications.

CAMILLO GOLGI
(1843-1926) was
an Italian doctor
and researcher. He
concentrated his
work on the nervous
system, though he also
strayed into malaria
research. Many of his
discoveries are named
after him, as is the
village of his birth.

THEODOR SCHWANN
(1810-1882) was a
German physicist
born in the town
of Neuss. He was
most productive
early in his career,
making discoveries
in digestion, the
nervous system and
metabolism, before
turning his attention
to theology later in life.

5 1831. We now know that the nucleus
contains the chromosomes of DNA and
is the seat of power from which our
genes regulate the rest of the cell.
A few years after Brown named the
nucleus, in 1837, the German scientist
Theodor Schwann was having lunch
with a fellow German researcher, the
botanist Matthias Schleiden. Their
conversation tu r ned to t he nucleus,
which had so far been seen only in
plants. Schleiden had observed that
new plant cells seemed to come
somehow from an existing nucleus.
Schwann, who had been studying
a nimal cells, remembered seeing
structures that could well be nuclei.
Excited, t he pair r ushed to
Schwann’s laboratory to look at
tadpole tissue. There were the nuclei:
a nimals must be made of cells too.
Both scientists wrote up their
findings, with Schleiden describing
cells as the ‘building blocks of life’,
and Schwann stating: “All living
things are composed of cells and
cell products.” It may seem obvious
now, but this ‘cell theory’ was
revolutionary: all life from algae to
aa rdva rks, bacteria to begonias, was
made of cells.

Wealth of discoveries
The subsequent decades of the 19th
century, as microscopes improved,
were fertile times for discovering the
components of cells and teasing apart
the differences between the cells of
animals, plants and bacteria.
Hooke, when coining the term cells,
had technically discovered the cell
wall in 1665. Human cells don’t have a
cell wall like pla nts a nd some bacteria,
but they do have a cell membrane, a
layer of lipids (fatty molecules),
proteins and other components.
Though it was clear that something
must su r round a nimal cells, it wasn’t
until 1855 that the doctor Robert
Remak found a way of hardening the
membrane so he could see it clearly.
About 70 per cent of the volume of
the cell is cytosol, a colourless liquid
t hat is mostly water, plus salts a nd
organic molecules. Together with
components called organelles, cytosol
makes up the cell’s cytoplasm –

The great minds who harnessed cutting-edge
technology of the time to explore cells

CAST OF CHARACTERS


THE FUNDAMENTALS OF LIFE

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