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
Dense regular connective tissue in DCRT elastic fibers are completely absent. Dense regular connective tissue has great tensile strength that resists pulling forces especially well in one direction. DRCT has a very poor blood supply, which is why damaged tendons and ligaments are slow to heal. Dense regular connective tissue Dense regular connective tissue provides connection between different tissues in the human body. The collagen fibers in dense regular connective tissue are bundled in a parallel fashion. Dense regular connective tissue (DRCT) is divided into white fibrous connective tissue and yellow fibrous connective tissue, both of which occur in two forms: cord arrangement and