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