Define Glomerular Filtration Rate (GFR)
Glomerular Filtration Rate (GFR) is defined as the amount of filtrate formed by the kidneys per minute. It measures the volume of blood plasma that is filtered through the glomerulus into the Bowman's capsule.
In a healthy individual, GFR is approximately 125 ml/minute, which amounts to about 180 litres per day. This filtration is the first step in urine formation and is carried out by the glomerulus using glomerular capillary blood pressure.
Explanation
The textbook directly defines GFR as 'the amount of the filtrate formed by the kidneys per minute.' The context provides the numerical value (125 ml/minute or 180 litres/day) for a healthy individual and explains that this filtration process occurs through the glomerulus into Bowman's capsule.