The A and IB and lengths in stretched or contracted horseshoe crab skeletal muscle.
D000818:Animals; D001181:Arthropods; D003445:Crustacea / Q000033:anatomy & histology*; D006737:Horseshoe Crabs; D009119:Muscle Contraction; D018482:Muscle, Skeletal; D009132:Muscles / Q000033:anatomy & histology*
CRUSTACEA/anatomy and histology; MUSCLES/anatomy and histology