filled with many fibrils, which are assemblies
of actin and myosin, the proteins of motion.
When a muscle contracts, the filaments of
actin and myosin slide past each other and
decrease the overall length of the complex.
Muscle contraction. The view through a light
microscope of rabbit muscle fibers, relaxed
(above) and contracted (below).
Less philosophical questions, but more
immediate ones for the cook, have been raised
by the changing quality of meat over the last
few decades. Thanks to the industrial drive
toward greater efficiency, and consumer
worries about animal fats, meat has been