Resting Membrane Potential Overview

<p>It occurs when chemical and electrical driving forces are equal and opposite (D)</p> Signup and view all the answers

<p>Intracellular potassium concentrations exceed extracellular concentrations (A)</p> Signup and view all the answers

<p>The concentration gradient and electrical force are equal and opposite. (A)</p> Signup and view all the answers

<p>It directly utilizes ATP to pump ions against their gradients. (C)</p> Signup and view all the answers

<p>The electrochemical gradient of another ion. (C)</p> Signup and view all the answers

<p>It can cause cells to either swell or shrivel depending on solute concentrations. (A)</p> Signup and view all the answers

<p>To facilitate the movement of water molecules. (B)</p> Signup and view all the answers

<p>Sevenfold reduction in water permeability of cell membranes. (C)</p> Signup and view all the answers

<p>Higher capacitative current corresponds with higher ionic current, maintaining membrane potential. (B)</p> Signup and view all the answers

<p>Antiport involves the movement of one solute against its gradient while another is moved down its gradient, whereas symport moves both against their gradients. (D)</p> Signup and view all the answers

A model describing the cell membrane as a fluid structure with a phospholipid bilayer and embedded proteins. The phospholipids form a barrier to ions and molecules, while proteins provide channels for transport and communication.

The difference in electrical charge between the inside and outside of a cell membrane. It is determined by the distribution of charged ions across the membrane.

The ability of a membrane to store electrical charge. This property is essential for cell signaling and communication.

The electrical potential at which the chemical and electrical forces driving ion movement across a membrane are equal and opposite.

The difference in concentration of potassium ions (K+) across the cell membrane, with a higher concentration inside the cell than outside.

The equilibrium potential is reached when the concentration gradient and the electrical force acting on an ion are equal and opposite, resulting in no net movement of the ion across the membrane.

The Na/K pump actively transports sodium ions out of the cell and potassium ions into the cell, using energy from ATP. This creates an imbalance in cation movement, making the pump electrogenic and contributing to the resting membrane potential.

Secondary active transport uses the energy stored in the electrochemical gradient of one ion to drive the transport of another solute against its concentration or electrochemical gradient.

Exchange, also known as antiport, is a type of secondary active transport where two molecules move in opposite directions across the membrane.

Cotransport, also known as symport, is a type of secondary active transport where two molecules move in the same direction across the membrane.

Osmosis is the net movement of solvent molecules, such as water, through a semi-permeable membrane into a region of higher solute concentration. This movement can cause cells to shrivel or swell due to osmotic pressure.

Aquaporins are channels that facilitate water movement across the membrane, and they are expressed in the nervous system.

The membrane can be considered as an RC circuit, where the capacitance represents the cell membrane and the resistance represents the ionic channels. As capacitative current increases, ionic current also increases, maintaining membrane potential.