Join the lil-help community to get work done and help others: Ask questions from the community Help others by answering questions Earn cash when you reach expert status PhysioEx Exercise 9 Renal System Physiology Worksheet Asked by maddy 4 years ago Effect of Arteriole Diameter on Glomerular Filtration 1.
The nephron The kidneys transport substances by three vectorial processes. Vectorial processes are characterized by their direction and size only Fig. Black arrows indicate three vectorial transporting processes in a nephron: Tubular reabsorption is the net movement of water and solute from the tubular lumen to the tubule cells and to the peritubular capillaries, and 3.
Tubular secretion represents the net addition of solute to the tubular fluid.
The final excretion rate of the substance s in the urine is called net-flux, Js, in Fig. Nephron anatomy The functional unit is the nephron. Each human kidney contains 1 million units at birth.
The distal tubule ends in a collecting duct together with tubules from several other nephrons. The kidney average normal weight g consists of a cortex and a medulla. The medulla is composed of renal pyramids, the base of which originates at the corticomedullary junction.
Each pyramid consists of an inner zone the papilla and an outer zone. The outer zone is divided into the outer medullary ray and the inner ray. The rays consist of collecting ducts and thick ascending limbs of the nephron.
A kidney lobulus is a medullary ray with adjacent cortical tissue.
A kidney lobule is a pyramid with adjacent cortical tissue. The loop of Henle is a regulating unit. Actually, the Henle loop consists of the proximal pars recta, the thin Henle loop and the distal pars recta, which ends at the level of macula densa.
The thin descending limb contains a water channel called aquaporin 1 in both the luminal and the basolateral membrane.
The last segment of the thick ascending limb is called the macula densa. The juxtaglomerular JG apparatus include the macula densa and granular cells of the afferent and efferent arterioles.
Granular cells are modified smooth muscle cells that produce and release renin. The distal tubule is convoluted from the macula densa of the JG apparatus Fig.
Several collecting ducts join to empty through the duct of Bellini into a renal cup or calyx in the renal pelvis. The superficial nephron represented on the left side of Fig.
The total inner surface area of all the glomerular capillaries is approximately m2. Mesangial and endothelial cells in the glomerulus secrete prostaglandins and exhibit phagocytosis. Many vasoconstrictors contract the mesangial cells, reduce the gomerular filtration coefficient Kf — see later and thus also GFR.Chapter Study Objectives · To define the concepts: Nephron, glomerular filtration, tubular secretion and reabsorption, renal lobulus, renal plasma clearance, osmolar clearance, tubular passage fraction, reabsorption fraction, excretion fraction, filtration fraction, plasma extraction fraction, proximal and distal system, glomerular propulsion pressure, net filtration pressure, renal.
Net filtration pressure is the sum of hydrostatic and colloid osmotic forces that either favour or oppose filtration across the glomerular capillaries. These forces include: (1) Hydrostatic pressure inside the glomerular capillaries (Pg) which promotes filtration.
4. the glomerular filtration rate normally ranges from You correctly answered: b. renal tubule length 3. Which of the following does not have a significant impact on the glomerular filtration rate?
You correctly answered: d.
2. 80 to ml/min. 05/26/13 page 3. 1. The glomerular filtration rate could increase.2/5(4). The purpose of this study was to examine the relationship of insulin resistance to glomerular hemodynamics and dietary salt intake in 10 older (68±6 years), obese (body mass index, 31±4 kg/m2), mildly hypertensive (±8/82±2 mm Hg), sedentary subjects without clinical evidence of .
An absolute, supraphysiologic elevation in GFR is observed early in the natural history in 10%–67% and 6%–73% of patients with type 1 and type 2 diabetes, respectively. Moreover, at the single-nephron level, diabetes-related renal hemodynamic alterations—as an adaptation to reduction in.
Heart failure develops when the heart, via an abnormality of cardiac function (detectable or not), fails to pump blood at a rate commensurate with the requirements of the metabolizing tissues or is able to do so only with an elevated diastolic filling pressure.
See the image below.