Across
- 2. system made up of the brain and the spinal cord.
- 4. a system that transports materials through blood using vessels.
- 7. a tubelike structure of neurons that sends signals to and from the brain.
- 8. a group of similar types of cells that work together to carry out specific tasks.
- 9. microscopic sacs or pouches at the end of the bronchioles where gas exchange occurs.
- 10. the basic functioning unit of the nervous system; a nerve cell.
- 11. a process in which food is physically broken into smaller pieces.
- 12. a large muscle below the lungs that contracts and relaxes as air moves into and out of your lungs.
- 14. the main organs of the respiratory system.
- 17. a type of vascular tissue that carries water and dissolved nutrients from the roots to the stem and the leaves.
- 19. the process by which cells become different types of cells.
- 23. a tube that is held open by C-shaped rings of cartilage; connects the larynx and the bronchi.
- 24. a part of food used by the body to grow and survive.
- 25. fingerlike projections, many of which cover the folds of the small intestine.
- 26. the part of an organism that gathers, processes, and responds to information.
- 29. a vessel that carries blood away from the heart.
- 30. a vessel that carries blood toward the heart.
- 31. muscle found only in the heart.
- 32. the lower two chambers of the heart.
- 36. system made of sensory and motor neurons that transmit information between the central nervous system (CNS) and the rest of the body.
- 41. where two or more bones meet.
- 42. a tubelike passageway at the top of the throat that receives air, food, and liquids from the mouth or nose.
- 43. a tiny blood vessel that delivers supplies to an individual cell and takes away waste materials.
Down
- 1. strong body tissue that can contract in an orderly way.
- 3. a muscular tube that connects the mouth to the stomach.
- 4. a process in which chemical reactions break down pieces of food into small molecules.
- 5. the upper two chambers of the heart.
- 6. a group of organs that work together and perform a specific task.
- 7. involuntary muscle named for its smooth appearance.
- 13. special structures in all parts of the sensory system that detect stimuli.
- 15. two narrow tubes that carry air into the lungs from the trachea.
- 16. a series of chemical reactions that convert light energy, water, and carbon dioxide into the food-energy molecule glucose and give off oxygen.
- 18. a fluid-filled internal cavity surrounded by muscle tissue.
- 20. the tissue that connects bones to other bones.
- 21. a thick, hard outer covering; protects and supports an animal’s body.
- 22. a group of different tissues working together to perform a particular job.
- 27. a system that transports blood and other fluids into open spaces that surround organs in the body.
- 28. specialized plant tissue composed of tubelike cells that transports water and nutrients in some plants.
- 33. a type of vascular tissue that carries dissolved sugars throughout a plant.
- 34. waves of muscle contractions that move food through the digestive tract.
- 35. the mechanical and chemical breakdown of food into small particles and molecules that your body can absorb and use.
- 37. the system that collects and eliminates wastes from the body and regulates the level of fluid in the body.
- 38. the amount of energy it takes to raise the temperature of 1 kg of water by 1°C.
- 39. the part of your nervous system that detects or senses the environment.
- 40. a small opening in the epidermis, or surface layer, of a leaf.