Renal Physiology: Regulation of Glomerular Filtration Rate

What is the primary function of the urinary system?

To filter blood and convert filtrate into urine.

Describe the composition of the bladder.

The bladder is an expandable and muscular sac.

Where are the kidneys located in the body?

The kidneys are located along the posterior abdominal wall and are retroperitoneal.

What is the function of the fibrous capsule surrounding the kidney?

The fibrous capsule maintains the kidney's shape and protects it from trauma. Signup and view all the answers

What is the role of perinephric fat (adipose capsule) around the kidney?

Perinephric fat provides cushioning and stabilization for the kidney. Signup and view all the answers

What is the function of renal fascia in relation to the kidney?

The renal fascia anchors the kidney to surrounding structures. Signup and view all the answers

What is the mechanism by which sympathetic nervous system decreases GFR?

Severe vasoconstriction of afferent and efferent arterioles Signup and view all the answers

How does atrial natriuretic peptide (ANP) increase GFR?

By stretching (vasodilating) the afferent arteriole Signup and view all the answers

What is the significance of the transport maximum (TM) in renal physiology?

It is the maximum amount of a substance that can be reabsorbed (or secreted) across the tubule epithelium. Signup and view all the answers

Define renal threshold.

The max plasma concentration of a substance that can be transported in the blood without being excreted in urine. Signup and view all the answers

Which part of the nephron is responsible for reabsorbing nutrients completely?

Proximal convoluted tubule (PCT) Signup and view all the answers

In which part of the nephron can water leave but solutes cannot?

Descending limb of the nephron loop Signup and view all the answers

What is the role of antidiuretic hormone (ADH) in the regulation of water reabsorption?

It causes the insertion of aquaporins in the apical membranes of principal cells in the collecting ducts. Signup and view all the answers

What is the driving force that pushes water and some dissolved solutes out of the blood of the glomerulus into the capsular space?

Glomerular Hydrostatic (blood) pressure (HPG) Signup and view all the answers

How does aldosterone regulate sodium reabsorption in the collecting ducts?

It promotes the synthesis of luminal Na+ and K+ channels, and basolateral Na+-K+ ATPases. Signup and view all the answers

What is the pressure exerted by the blood due to unfiltered dissolved solutes, which opposes filtration by pulling fluid back into the blood?

Blood Colloid Osmotic Pressure (OPG) Signup and view all the answers

What is the main function of aldosterone in the urinary system?

To increase blood pressure and decrease potassium levels. Signup and view all the answers

What is the primary function of the thick segment of the ascending limb of the nephron loop?

To utilize the Na+-K+-2Cl- symporter and Na+-H+ antiporter for ion transport. Signup and view all the answers

How is the Net Filtration Pressure (NFP) calculated?

NFP = HPG - (OPG + HPC) Signup and view all the answers

What is the Glomerular Filtration Rate (GFR)?

Glomerular Filtration Rate (GFR) is the rate at which the volume of filtrate is formed per unit time. Signup and view all the answers

How does an increase in Net Filtration Pressure (NFP) influence the Glomerular Filtration Rate (GFR)?

An increase in NFP leads to an increase in GFR. Signup and view all the answers

What is the function of Renal Autoregulation in regulating the Glomerular Filtration Rate (GFR)?

Renal Autoregulation allows the kidneys to produce urine at a constant rate despite fluctuations in systemic blood pressure. Signup and view all the answers