Relier Pairs Tissues, Organs, and Body SystemsVersion en ligne Review the tissue, organ, and body systems. par Janelle Ruiz 1 Circulatory System 2 Respiratory System 3 Muscular System 4 Epithelial Tissue 5 Nervous System 6 Connective Tissue 7 Digestive System Brain, spinal column, axons Lines organs and protects inside of body from outside world Heart, veins, capillaries Supports organs and joins tissue Responsible for gas exchange (oxygen- carbon dioxide) with the outside environment