Comparison of transport

Passive Processes Movement of substances down the concentration gradient (from high to low until equilibrium is reached). No energy is required for any of this processes.

Active Processes

Cellular energy (ATP) is used to pump substances against (up) the concentration gradient – from low concentration of solute to high concentration of solute.

Comparison Chart

Major mechanisms by wich molecules cross membranes

Both channel and carrier proteins may facilitate diffusion requiring no energy or may involve active transport requiring energy from ATP.

Sources:

MESCHER, Antony. Junqueira's Basic Histology. 13th edition. 2013. ISBN 978-1-259-07232-1.

Notes: Biophysics. prof. RNDr. Evžen Amler, CSc. 2nd faculty of medicine, Charles University, Prague. Czech Republic.

Cytology I Lecture, Prof. Vajner