1. The filtration membrane contain 3 layers name two of them a. b. 2. The glomer
ID: 3513966 • Letter: 1
Question
1. The filtration membrane contain 3 layers name two of them a. b. 2. The glomerulus contains an afferent and efferent arteriole, why are they both arterioles? 3. Which pressure promotes filtration in the glomerulus? two opposing pressures what are the and_ 4. GFR is autoregulated by intrinsic and extrinsic factors. The dominate intrinsic factor is IF GFR is low, what does this intrinsic factor do? 5. The backup intrinsic factor is called the the cells control this system. What are these cells monitoring? 6. Increased levels of NaCI in the distal convoluted tubule tell you that GFR is ( high or low)? 7. The extrinsic regulator GFR is or decrease GFR? ????????sy em. Does this system increase ??????? 8. f MAP exceeds 180mmHg, what happens to GFR?Explanation / Answer
1. There are three layers of the filtration membrane in the kidney-
2. Arterioles are the smallest blood vessels that carry blood in them . They have all the three layers of a blood vessels- tunica interna, tunica media , and tunica externa. Tunica media is the thin layer that contains muscle fibres. These muscle fibres helps the arterioles to constrict and dilate in response to sympathetic stimulation and hormone(angiotensin II) levels . As the glomerular filtration rate is to be modulated according to the blood pressure of the body, arterioles are present in the glomerulus rather than capillaries.
3. The force (pressure) that favours the filtration process are-
The pressures that opposes the filtration are-
4. The dominant intrinsic factor for the regulation of the blood flow through the gloerulus is the renal autoregulation. This regulates the diameter of the afferent arteriole, which in turn regulate the GFR.
If the GFR is low , there is the dilatation in the afferent arterioles, which causes increased GFR.
5. The backup intrinsic factor is the Macula densa. These have packed specialized cells that are sensetive to the concentrations of NaCl in the distal convulated tubules, If the NaCl concentration decreases, macula densa sends a signal which-
Decreases the resistance to the blood flow in the afferent arterioles, which increases the glomerular hydrostatic pressure.
6. NaCl in the DCT indicates that there is less absorption in the PCT and the loop of henle. Increased levels of Na+ ions in the filtrate also draws excess amount of water into the tubules , which ultimately decreases the GFR.
7. The extrinsic factor that regulates the GFR is the Renin-Angiotensin-Aldosterone system. It helps in increasing the blood pressure.
If low GFR is detected , which is indicative of decreased blood pressure, Renin secretion from the Juxtaglomerular cells to blood occurs. This Renin acts as an enzyme, which converts angiotensinogen to angiotensin I , which is later converted to angiotensin II . Angiotensin II is a powerful vasoconstrictors , which causes increased blood pressure.
Angiotensin II also stimulates Aldotsterone in the adrenal cortex, which causes increased absorption of sodium and water and increased excretion of potassium from the kidneys , which also increases the blood pressure.
8. Mean Arterial Presuure (MAP) of 180mmHg, suggests high blood pressure, which means there is high glomerular hysdrostatic pressure , which means more filterate will be formed . Thus high values of MAP increases the GFR too.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.