Plants and animals have structures for respiration, digestion, waste disposal, and transport of materials. As a basis for understanding this concept:
Students know the sequential steps of digestion and the roles of teeth and the mouth, esophagus, stomach, small intestine, large intestine, and colon in the function of the digestive system.
Elements and their combinations account for all the varied types of matter in the world. As a basis for understanding this concept:
Students know the common properties of salts, such as sodium chloride (NaCl).