1.List 3 substances that MUST pass through the cell membrane. Explain. 2. Hospital patients are usually given intravenous fluid(IVs) to maintain proper levels of Water/salt in the body. If a manufacturer accidentally prepared a batch of IV fluid that had distilled water, harm to the patient could result. Explain how an IV filled with distilled water could harm patients.

Students in biology are studying the macromolecules of life. they used a calorimeter to determine the calories in various types of food. once the lab was completed, the students ate the left over food samples. monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. elaborate on what happened chemically while chewing the saltine. include the macromolecules present.