Exam 3: The Plasma Membrane and Membrane Potential

Under an electron microscope, the plasma membrane appears as a trilaminar structure consisting of two dark layers separated by a light middle layer.

Membrane carbohydrates in the plasma membrane combine with fats to form ____________________.

In ____________________ transport, sodium and the accompanying molecule are moved in opposite directions across the membrane.

Net diffusion of water down its own concentration gradient toward an area of higher solute concentration is known as ____________________.

With secondary active transport, energy is directly required by the carrier to move a substance uphill against a concentration gradient.

At resting membrane potential, passive and active forces exactly balance each other so there is no net movement of ions across the membrane.

By active transport a substance moves from an area of ____________________ concentration to an area of ____________________ concentration.

The membrane potential that exists when the concentration and electrical gradients for a given ion exactly counterbalance each other is known as the ____________________.

Pinocytosis, or "cell drinking," refers to the process of a cell engulfing a large, solid particle and bringing it within the contents of the cell.

In which process is energy required but not directly used to produce movements against concentration gradients?

Assuming a membrane is only water soluble and there is no significant hydrostatic pressure, water will osmose from

The predominant cation in the intracellular fluid is A-

Explain how the equilibrium potential for potassium is generated.

The electrical gradient for K⁺