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Fig. 2. Length/tension diagram for the m. hyoglossus of an adult Pogona
vitticeps. In these experiments, the tongue of the lizard was attached to
a force lever, its length was changed, the muscle was tetanically stimulated
and the forces were recorded. The length/tension diagram for P.
vitticeps is similar to that reported for other animals with typical
cross-striated muscle, showing a rapid increase in tension, a distinct optimal
length for contraction and a decrease in tension if the muscle is extended
beyond its optimal length.