Unit-VII Physics of Ion ChannelsBy abdulslambsn@gmail.com / June 14, 2025 Quiz 7 | Unit-VII Physics of Ion Channels Your Good Name: Your College Name: Morning/Evening/Private: Email: 1. Which physical principle best explains how ions pass through a channel down their electrochemical gradient? Newton’s Second Law Fick’s Law of Diffusion Pascal’s Principle Bernoulli’s Equation None 2. Which ion is most abundant outside the cell? K⁺ Na⁺ Cl⁻ Ca²⁺ None 3. The resting membrane potential of a typical neuron is approximately: +70 mV –70 mV 0 mV –20 mV None 4. Ion channels exhibit selectivity because: They are gated by voltage The membrane is semi-permeable The pore size and amino acids allow only certain ions The ions bind covalently to the channel None 5. Which of the following blocks voltage-gated Na⁺ channels? Lidocaine ATP Dopamine Glucose None 6. Voltage-gated ion channels open in response to: Hormone binding Changes in membrane potential ATP levels Cell growth None 7. Which equation calculates the equilibrium potential of a single ion across a membrane? Van’t Hoff equation Ohm’s law Nernst equation Einstein’s law None 8. Which ion contributes most to the resting membrane potential? Na⁺ Cl⁻ Ca²⁺ K⁺ None 9. Which structure allows passive movement of ions without using ATP? Sodium-potassium pump ATP synthase Ion channel Endocytosis vesicle None 10. What property allows ions to move through open channels? Concentration gradient only Electrical gradient only Electrochemical gradient Osmotic pressure None 11. The movement of ions through ion channels is: Active transport Passive transport Osmosis Endocytosis None 12. Ion channels in neurons open briefly and close again. This behavior is called: Tunneling Inactivation Polarization Fusion None 13. The gating of ion channels refers to: Direction of ion flow Ion selectivity Opening and closing of the channel Synthesis of ion channels None 14. Which ion is most abundant inside the cell? Na⁺ K⁺ Cl⁻ Ca²⁺ None 15. Which factor does not affect ion flow through a channel? Membrane voltage Ion size Oxygen level Concentration gradient None 16. Which law defines the current through an open ion channel based on voltage and conductance? Faraday’s law Ohm’s law Avogadro’s law Nernst equation None 17. What is the charge on a calcium ion (Ca²⁺)? +1 +2 -1 0 None 18. Patch clamp technique is used to: Block ion channels Record activity of individual ion channels Measure pH Observe mitochondria None 19. How does temperature affect ion channel conductivity? No effect Higher temp increases kinetic energy and ion movement It freezes the ions It destroys ion channels None 20. Which ion is involved in neurotransmitter release? Na⁺ K⁺ Cl⁻ Ca²⁺ None 21. What happens if extracellular K⁺ rises sharply? Membrane becomes more negative Membrane depolarizes ATP increases Na⁺ channels close permanently None 22. In ion channels, selectivity filter ensures: ATP production Voltage regulation Only specific ions pass Endocytosis None 23. Ion channels are mostly made of: Lipids Proteins Sugars DNA None 24. What type of ion channel opens in response to a ligand like acetylcholine? Voltage-gated Mechanosensitive Ligand-gated Stretch-gated None 25. How do ion channels contribute to action potentials? They generate ATP They release neurotransmitters They rapidly shift membrane voltage They break down neurotransmitters None 1 out of 3 Thanks For Submitting Your Quiz !!