THE NEXT BIG LEAP 
The next big leap in medicine may 
occur as researchers increasingly 
apply what they have learned about 
the world of the living cell to the prob- 
lems of disease. Although many of the 
features of cells have been scrutinized 
and are now quite familiar to students 
of biology, scientists still want to know 
more about the architecture of cells, 
as well as how cells move and grow, 
how they communicate with one 
another, and how they work — or fail 
to work. As scientists study cells in 
finer and finer detail, the relationship 
between cell malfunction and certain 
diseases becomes clearer. Cancer, 
for instance, is a derangement of cell 
growth. Normal cells stop dividing 
upon contact with other cells, but can- 
cerous cells multiply endlessly, as if 
their surface membranes can no longer 
perceive signals from nearby cells. If 
the still-cryptic signals that tell a cell 
when to divide and when to stop are 
deciphered, new approaches to 
cancer treatment could result. Other 
major health problems of today, 
including genetic disorders, heart dis- 
ease, and diabetes, may also yield 
to improved therapies as more is 
learned about the cell. 
The work is already under way. In 
the past 40 years, through a combi- 
nation of electron microscopy, bio- 
chemical analyses of cell parts, X-ray 
crystallography, and other techniques, 
cell biologists have looked inside the 
cell and revealed it to be a complex 
and highly organized entity. A typical 
cell is like a miniature body containing 
tiny organs, called organelles. One 
organelle is the command center, 
others provide the cell with energy, 
while still others manufacture proteins 
and other molecules that the cell 
needs to survive and to communicate 
with the world around it. The entire 
cell is enclosed in a fine skin, its sur- 
face membrane. This membrane not 
only keeps the cell intact, it also pro- 
vides portals that allow selected mole- 
cules into and out of the cell. 
This booklet describes the internal 
landscape of the cell and the work of 
some of the pioneers who first 
mapped its features. Much has been 
glimpsed, but much more remains to 
be seen. How, for instance, is the 
work of protein manufacture orches- 
trated within the. cel I ? What prompts 
a cell to divide? How does a human 
being, complete with eye, hair, bone, 
blood, skin, and nerve cells, arise 
from a single undifferentiated cell? 
Solving these cellular mysteries will 
require the concerted efforts of scien- 
tists from many disciplines, including 
anatomy, physiology, physics, and 
chemistry. Cell biologists of today 
can look forward to a future of discov- 
ery and refined understanding as they 
continue to reveal the living worlds 
within us. 
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