Cell Biology Membranes II: Passive and active transporters by Nathan H Lents, Ph.D. Reading Quiz Teach with this 1. Water molecules are unable to pass directly through a biological membrane because they have partial positive and partial negative charges. they do not have a charge. they are too large. the fatty acids inside the membrane are too close together. 2. Active transporters do not require an input of energy to allow molecules to pass through them. true false 3. Channels allow specific molecules to flow from areas of low concentration to areas of high concentration. from areas of high concentration to areas of low concentration. in either direction across a membrane. out of a cell, in order to build the concentration gradient. 4. People who suffer from chronic heartburn or indigestion may take a drug to reduce the discomfort. These drugs work by allowing ions to pass quickly through the cell’s membrane. completely blocking ions from passing through the cell’s membrane. slowing down the proton pumps in the stomach walls. speeding up the proton pumps in the stomach walls. 5. The sodium/potassium pump (Na+/K+ pump) actively moves these two different ions in opposite directions. This is known as a(n) gate. ATP. analgesic. antiport. 6. Acetylcholine is a neurotransmitter that causes muscles to contract by stimulating the sodium pump. inhibiting the potassium pump. opening sodium gates. stimulating the Na+/K+ pump. 7. In all cells of the human body, the concentration of _______ is higher inside the cells and the concentration of ________ is higher outside the cells. potassium; sodium sodium; ATP ATP; sodium protons; ATP 8. Which term is not related to active transport? ATP energy facilitated diffusion pumps Score Quiz
