Tubular reabsorption Reabsorption plays a major role than the secretion in the formation of urine. More than 90% of the water in the GF is reabsorbed as it passes through the tubules. Some substances such as sodium, glucose and amino acids are almost completely reabsorbed so that their concentration decreases almost to zero before the fluid becomes […]

Glomerular filtration Glomerular filtrate is the fluid that is filtered through the glomerular membrane into the Bowman’s capsule. Glomerular capillary membrane Glomerular capillaries are relatively impermeable to proteins so that the filtered fluid, glomerular fluid (GF) is essentially protein free and devoid of cellular elements. The glomerular capillary membrane has three layers: Endothelium of the capillary Basement

Formation of urine in the nephrons Three processes are involved in the formation of urine in the nephrons- Glomerular filtration, Tubular reabsorption, Tubular secretion.

Autoregulation of GFR & RBF in animals RBF and GFR remains almost relatively constant when the systemic arterial pressure changes from 75 mm Hg to 160 mm Hg. This ability of the RBF and GFR to resist severe changes in the arterial pressure is called as ‘autoregulation of RBF and GFR’. It is an intrinsic

Glomerular filtration rate (GFR) and RBF in animals Glomerular filtration rate (GFR) Glomerular filtration rate (GFR) is the quantity of GF formed each minute in all the nephrons of both the kidneys/kg body weight. In humans it is about 125 ml/min. Total quantity of GFR formed /day = 180 L. Over 99% of the filtrate

Juxtaglomerular apparatus or JG apparatus When the thick segment of the ascending limb of the loop of Henle returns to its glomerulus of origin in the cortex, it passes in the angle between afferent and efferent arterioles and continues as the distal tubule. The side of the tubule that faces the glomerulus comes in contact with

Blood supply and innervations of kidney in animals Blood supply to kidney Blood flow to the kidneys is normally 22% of the cardiac output. The renal artery enters the kidney and branches to form the interlobar arteries, arcuate arteries, interlobular arteries and afferent arterioles which lead to the glomerular capillaries, where large amount of fluid and

Nephron and types of nephron of animals Nephron Components The glomerular capsule (Bowman’s capsule) is the dilated blind end of the nephron and consists of the invaginated capillary tuft called as the glomerulus. In the mammals the blood from the renal artery is delivered to the afferent arteriole which divides into numerous glomerular capillaries. The

Kidney functions of animals Functions of kidney The important function of the kidneys is to rid the body of waste materials that are either ingested or produced by metabolism. To control the volume and composition of the body fluids. A balance between the intake and output is maintained in large part by the kidneys. This