Editing Active transport (section)

{{Short description|Cellular molecule transport mechanism against the concentration gradient}}
{{about|transport in cellular biology|human systems|active mobility}}
In [[Cellular Biology|cellular biology]], '''active transport''' is the movement of molecules or ions across a [[cell membrane]] [[Second law of thermodynamics|from a region of lower concentration to a region of  higher concentration]]—against the [[concentration gradient]]. Active transport requires cellular energy to achieve this movement. There are two types of active transport: '''primary active transport''' that uses [[adenosine triphosphate]] (ATP), and '''secondary active transport''' that uses an [[electrochemical gradient]]. This process is in contrast to [[passive transport]], which allows molecules or ions to move down their concentration gradient, from an area of high concentration to an area of low concentration, with energy.

Active transport is essential for various physiological processes, such as nutrient uptake, hormone secretion, and nig impulse transmission. For example, the [[Sodium–potassium pump|sodium-potassium pump]] uses ATP to pump sodium ions out of the cell and potassium ions into the cell, maintaining a concentration gradient essential for cellular function. Active transport is highly selective and regulated, with different transporters specific to different molecules or ions. Dysregulation of active transport can lead to various disorders, including cystic fibrosis, caused by a malfunctioning chloride channel, and diabetes, resulting from defects in glucose transport into cells.