Passive transport

From WikiMD's Wellness Encyclopedia

Passive transport is a type of cellular transport that does not require energy to move substances across cell membranes. It is a naturally occurring phenomenon and relies on the inherent kinetic energy and natural entropy of molecules to diffuse across a membrane.

Types of Passive Transport[edit | edit source]

There are three main types of passive transport:

  1. Simple diffusion: This is the process by which solutes are moved along a concentration gradient in a solution or across a semipermeable membrane.
  1. Facilitated diffusion: This process uses transport proteins to move other ions and small molecules across the cell membrane.
  1. Osmosis: This is the movement of solvent molecules through a selectively permeable membrane into an area of higher solute concentration, aiming to equalize the solute concentrations on the two sides.

Factors Affecting Passive Transport[edit | edit source]

Several factors can affect the rate of passive transport, including:

  • Temperature: Higher temperatures increase the energy and therefore the movement of the molecules, increasing the rate of diffusion.
  • Size of the molecules: Smaller molecules diffuse more quickly than larger ones because smaller molecules move faster due to having less mass.
  • Nature of the molecules: Polar molecules diffuse more slowly than non-polar molecules. Non-polar or lipid-soluble molecules pass through the membrane more easily than polar molecules.

Importance of Passive Transport[edit | edit source]

Passive transport is essential for many functions within the human body and in other living organisms. For example, it is necessary for the absorption of most of the water and nutrients cells need. It also helps to maintain the balance of various ions (both inside and outside the cells) which is necessary for nerve and muscle function.

Passive transport Resources
Wikipedia
WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD