SIMIAN CREASE: Normal palmar crease. SIMIAN CREASE: Simian crease. simian crease. A crease on the palm of the hand, so called because of its similarity to the transverse flexion crease found in some monkeys. Normally the palm of the hand at birth contains several flexion creases, two of which are separate and approx. transverse. When these two appear to fuse and form a single transverse crease, a simian crease is present.
Muscle contraction is the activation of tension-generating sites within muscle fibers. In physiology, muscle contraction does not mean muscle shortening because muscle tension can be produced without changes in muscle length such as holding a heavy book or a dumbbell at the same position.he termination of muscle contraction is followed by muscle relaxation, which is a return of the muscle fibers to their low tension-generating state. Muscle contractions can be described based on two variables: length and tension.
The heart controls its own contractions through electric impulse. Muscle fibers might get longer, shorter or stay the same during muscle contraction. An eccentric muscle contraction occurs when the muscle increases in length, such as when doing a push-up. concentric contraction occurs when the muscle decreases in length, such as when performing a bicep curl. An eccentric contraction occurs when the muscle increases in length, such as when doing a push-up. Ad. Muscle contractions can result in either movement or no movement.