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