| Flap 1 | Flap 2 |
| Cell | The basic unit of structure and function in a living thing. |
| Cell Membrane | The outside boundary of a cell. |
| Nucleus | The control center of the cell that directs the cell's activities and contains information that determines the cell's characteristics. |
| Cytoplasam | The area in a cell between the cell membrane and the nucleus. |
| Tissue | A group of similar cells that perform the same function. |
| Muscle Tissue | A body tissue that contracts or shortens, making body parts move. |
| Nerve Tissue | A body tissue that carries messages back and forth between the brain and every otherp art of the body. |
| Connective Tissue | A body tissue that provides support for the body and connects all of its parts. |
| Epithelial Tissue | A body tissue that covers the surfaces of the body, inside and out. |
| Organ | A structure in the body that is composed of different kinds of tissue. |
| Oragn System | A group of organs that work together to perform a major function in the body. |
| Digestion | The process by which the body breaks down food into small nutrient molecules. |
| Absorption | The process by which nutrient molecules pass through the wall of the digestive system into the blood. |
| Saliva | The fluid released when the mouth waters that plays an important role in both mechanical and chemical digestion. |
| Enzyme | A protein that speeds up chemical reactions in the body. |
| Epiglottis | A flap of tissue that seals off the windpipe and prevents food from entering. |
| Esophagus | A muscular tube that connects the mouth to the stomache. |
| Mucus | A thick slippery substance produced by the body. |
| Peristalsis | Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system. |
| Stomach | A J-Shaped muscular pouch located in the abdomen that expends to hold all of the food that is swallowed. |
| Small intestine | The part of the digestive system in which most chemical digestion takes place. |
| Liver | The largest and heaviest organ inside the body. |
| Bile | A substance produced by the liver that breaks up fat particles. |
| Gallbladder | The organ that store bile after it is produced by the liver. |
| Pancreas | A triangulat organ that produces enzymes that flow into the small intestine. |
| Villus | Tiny-finger shaped structures that cover the inner surface of the small intestine and provides a large surface area through which digested food is absorbed. |
| Large intestine | The last section of the digestive system, where water is absorbed from food and the remaining material is eliminated from the body. |
| Rectum | A short tube at the end of the large intestine where watse material is compressed into a solid form beffore being eliminated |
| Anus | A muscular opening at the end of the rectum through which digestive waste material is eliminated from the body. |
