Relier Pairs HUMAN BIOLOGYVersion en ligne LINK NAME AND DEFINITION par Guy Kruse 1 connective tissue 2 hormone 3 organ system 4 epithelial tissue 5 nervous tissue 6 cardiovascular system 7 cells 8 tissue 9 muscle tissue 10 organ A chemical messenger molecule. Structure made of two or more tissues that work together. Organs that work together to serve a common purpose. Organ system made up of the heart, blood, and blood vessels. Basic unit of structure and function of a living organism; the basic unit of life. Group of nerve cells that sense stimuli and transmit signals; found in brain, spinal cord, and nerves. Bands of cells that contract and allow movement. Group of cells that are all involved in supporting and binding other tissues of the body; i.e. tendon, cartilage, bone, and blood. Group of similar cells working together. Layers of tightly packed cells that line the surfaces of the body.