cells and body systems

1. either of the two saclike respiratory organs in the thorax of humans and the higher vertebrates.
7. a group of organs that perform a certain task
9. either of a pair of bean-shaped organs in the back part of the abdominal cavity that form and excrete urine. bladder a membranous sac or organ serving as a receptacle for a fluid or air.
12. muscular wall separating two cavities or limiting a cavity.
13. a specialized part of a cell having some specific function; a cell organ.
15. the tendency of a fluid, usually water, to pass through a semipermeable membrane into a solution
17. part of the central nervous system enclosed in the cranium of humans and other vertebrates neuron a specialized, impulse-conducting cell that is the functional unit of the nervous system
18. the anterior and largest part of the brain, consisting of two halves or hemispheres and serving to control movements and actions
20. to act or perform again
21. one of the minute, wormlike processes on certain membranes

2. the cord of nerve tissue extending through the spinal canal of the spinal column
3. one of the minute blood vessels between the terminations of the arteries and the beginnings of the veins.
4. a form of life composed of mutually interdependent parts that maintain various vital processes.
5. having or consisting of a single cell.
6. an aggregate of similar cells and cell products forming a definite kind of structural material with a specific function, in a multicellular organism.
8. act of diffusing; state of being diffused
10. blood vessels that carry blood away from the heart
11. trachea the tube in humans extending from the larynx to the bronchi nerves
13. grouping of tissues into a distinct structure,that performs a specialized task.
14. to act one upon another
16. a soft, fatty, vascular tissue in the interior cavities of bones that is a major site of blood cell production
19. either of the two main branches of the trachea