Systole heart beats—is cued by messages from the brain, reflecting the brain's responses to conditions of the body, such as pain, emotional stress, level of activity, and to ambient conditions including external temperature, time of day, etc. Electrical systole opens voltage-gated sodium, potassium and calcium channels in cells of myocardium tissue. Subsequently, a rise in intracellular calcium triggers the interaction of actin and myosin in the presence of ATP which generates mechanical force in the cells in the form of muscular contraction, or mechanical systole. The contractions generate intra-ventricular pressure, which is increased until it exceeds the external, residual pressures in
101 Things Removed from the Human Body 101 Things Removed from the Human Body 101 Things Removed from the Human Body and 101 More Things Removed from the Human Body is a British "shockumentary" series directed by Eric Schotz, which is narrated by Mitch Lewis. The program features tales of foreign objects that have been removed from human bodies in the form of a countdown from 101 to 1. Items included are javelins, a boat anchor, a bicycle pump, a bag of nails, an ice pick, and a human body. The documentary series was first broadcast on Sky One in October 2003. When the show was re-broadcast