What are the main components of the urinary system?
The kidneys and accessory structures.
p.36
Reabsorption and Secretion Processes
What role does secretion play in the urinary system?
To remove waste products and excess ions from the blood into the filtrate.
p.10
Nephron Structure and Function
What is the role of the juxtaglomerular apparatus in the nephron?
To regulate blood flow and pressure through the nephron.
p.19
Nephron Structure and Function
What do the foot processes of podocytes do?
They wrap around the endothelium and form filtration slits.
p.29
Reabsorption and Secretion Processes
How does the composition of filtrate entering the proximal tubules compare to plasma?
It is similar in ion composition to plasma.
p.19
Nephron Structure and Function
How do filtered substances enter the tubule lumen?
They pass through endothelial pores and filtration slits.
p.29
Reabsorption and Secretion Processes
What is the relationship between sodium (Na+) concentration in the filtrate and in proximal tubule cells?
The [Na+] in filtrate is higher than that in proximal tubule cells.
p.37
Reabsorption and Secretion Processes
What is the formula for excretion rate?
Excretion rate = filtration - reabsorption + secretion.
p.20
Glomerular Filtration
What does colloid osmotic pressure in glomerular capillaries result from?
The presence of plasma proteins.
p.36
Regulation of Plasma Volume and Blood Pressure
What is the effect of aldosterone on secretion?
It increases the secretion of potassium and the reabsorption of sodium.
p.16
Nephron Structure and Function
What changes occur in filtrate volume along the nephron?
Filtrate volume decreases as it moves through the nephron.
p.32
Reabsorption and Secretion Processes
What does transport maximum (T m) refer to?
The transport rate at saturation.
p.10
Nephron Structure and Function
What is the juxtaglomerular apparatus?
The site where the initial portion of the distal tubule contacts with the afferent and efferent arterioles of the nephron.
p.8
Nephron Structure and Function
What is the function of the vasa recta?
It is part of the nephron's vascular system, associated with the loop of Henle.
p.29
Reabsorption and Secretion Processes
How does sodium (Na+) enter the proximal tubule cells?
Through membrane proteins, moving down its electrochemical gradient.
p.15
Nephron Structure and Function
What is the role of the afferent arteriole in the urinary system?
It brings blood to the glomerulus for filtration.
p.36
Reabsorption and Secretion Processes
What substances are commonly reabsorbed during the reabsorption process?
Water, glucose, amino acids, and ions like sodium and potassium.
p.36
Nephron Structure and Function
What is the significance of the loop of Henle in reabsorption?
It creates a concentration gradient that allows for the reabsorption of water and salts.
p.30
Reabsorption and Secretion Processes
How does Na+ move in relation to its electrochemical gradient?
Na+ moves down its electrochemical gradient.
p.19
Nephron Structure and Function
What is the lumen of Bowman's capsule?
The space where filtered material collects after passing through the filtration barrier.
p.16
Nephron Structure and Function
How does osmolarity change along the nephron?
Osmolarity increases as filtrate moves from the proximal tubule to the collecting duct.
What are the two main regions of the kidney?
The outer cortex and the inner medulla.
p.23
Intrinsic Control of GFR
What is the myogenic response in the context of GFR regulation?
An intrinsic ability of vascular smooth muscle to respond to pressure changes.
What is the primary function of the urinary system regarding plasma pH?
Regulation of plasma hydrogen ion concentration (pH).
p.5
Nephron Structure and Function
What are nephrons?
The functional units of the kidney responsible for urine formation.
p.13
Nephron Structure and Function
What are the basic renal exchange processes in the urinary system?
Glomerular filtration, reabsorption, and secretion.
p.22
Glomerular Filtration Rate (GFR)
What are the two main factors that influence GFR?
Net filtration pressure and filtration coefficient.
p.2
Reabsorption and Secretion Processes
What types of wastes does the urinary system excrete?
Metabolic wastes (e.g. creatinine, urea, uric acid) and foreign substances (e.g. drugs).
p.31
Reabsorption and Secretion Processes
Are there active transporters for urea reabsorption in the proximal tubules?
No, there are no active transporters for urea reabsorption.
p.27
Nephron Structure and Function
What is the primary function of the collecting duct in the urinary system?
To collect urine from the nephron and transport it to the renal vein.
p.30
Reabsorption and Secretion Processes
What is the role of SGLT in glucose reabsorption?
It pulls glucose into the cell against its concentration gradient using Na+.
p.18
Nephron Structure and Function
What is Bowman’s capsule?
A structure in the kidney that encases the glomerulus and collects filtrate.
p.31
Reabsorption and Secretion Processes
What establishes the concentration gradient of urea in the proximal tubule?
Reabsorption of Na+ and other solutes makes the interstitial fluid more concentrated than the filtrate.
What is the role of the peritubular capillaries?
To allow reabsorbed molecules to enter the blood.
p.34
Reabsorption and Secretion Processes
What does glucose reabsorption illustrate in the urinary system?
The concept of renal transport saturation.
p.33
Reabsorption and Secretion Processes
What happens when the transport maximum for glucose is reached?
The transport becomes saturated, and further increases in plasma glucose do not increase the transport rate.
p.26
Extrinsic Control of GFR
What effect do sympathetic neurons have on vascular smooth muscle?
They cause vasoconstriction via alpha receptors.
What is the purpose of the urinary bladder?
To store urine until it is excreted.
p.15
Reabsorption and Secretion Processes
What are the three main processes involved in urinary excretion of solute?
Filtration, reabsorption, and secretion.
p.22
Glomerular Filtration Rate (GFR)
What is the volume of fluid that filters into the Bowman’s capsule per unit time called?
Glomerular filtration rate (GFR).
p.30
Reabsorption and Secretion Processes
What does GLUT facilitate?
Facilitated diffusion of glucose.
p.12
Reabsorption and Secretion Processes
What process occurs in the proximal tubule?
Reabsorption: lumen to blood.
What is the anatomical position of the kidneys?
They lie in shallow depressions against the posterior abdominal wall and are retroperitoneal.
p.28
Reabsorption and Secretion Processes
What happens to the concentrations of other solutes as fluid volume in the lumen decreases?
Concentrations of other solutes increase.
p.27
Glomerular Filtration
What is the role of the glomerulus in the urinary system?
To filter blood into the lumen of the nephron.
p.28
Reabsorption and Secretion Processes
What are the two pathways for tubular reabsorption?
Transcellular transport and paracellular pathway.
p.18
Nephron Structure and Function
What is the lumen of Bowman’s capsule?
The space within Bowman’s capsule where filtered material collects.
p.28
Nephron Structure and Function
What is the role of the tubular epithelium in reabsorption?
It facilitates the transport of substances across membranes.
p.33
Reabsorption and Secretion Processes
What is the relationship between plasma glucose concentration and glucose filtration in the kidneys?
Filtration of glucose is directly proportional to the plasma glucose concentration.
What is the function of the kidneys in the urinary system?
To filter blood and produce urine.
What is the role of the ureters?
To transport urine from the kidneys to the urinary bladder.
p.29
Reabsorption and Secretion Processes
What is the primary driving force for most renal reabsorption?
Active transport of sodium (Na+ - K+ - ATPase).
p.26
Extrinsic Control of GFR
When does sympathetic activity increase to control GFR?
When mean arterial pressure (MAP) falls below 80 mm Hg.
p.23
Intrinsic Control of GFR
What is tubuloglomerular feedback?
A paracrine control on the fluid flow through the loop of Henle.
p.36
Nephron Structure and Function
Where does most reabsorption occur in the nephron?
In the proximal convoluted tubule.
p.26
Extrinsic Control of GFR
What is the role of Angiotensin II in the urinary system?
It acts as a potent vasoconstrictor.
p.14
Nephron Structure and Function
What are the basic renal exchange processes in the urinary system?
Glomerular filtration, reabsorption, secretion, and excretion.
p.21
Nephron Structure and Function
What is the role of the afferent arteriole in the urinary system?
It supplies blood to the glomerulus.
p.17
Glomerular Filtration
What is the composition of the filtrate in glomerular filtration?
Filtrate is composed only of water and dissolved solutes.
p.13
Reabsorption and Secretion Processes
What occurs during reabsorption in the urinary system?
The selective transport of molecules from the lumen back to the blood.
p.29
Reabsorption and Secretion Processes
What type of transporter is Na+ - K+ - ATPase?
An active transporter and membrane protein.
p.14
Reabsorption and Secretion Processes
What is reabsorption in the context of renal processes?
The process of moving substances from the lumen back into the blood.
p.6
Nephron Structure and Function
What is a key functional difference between cortical and juxtamedullary nephrons?
Juxtamedullary nephrons help maintain osmotic gradients in the medulla.
What structures emerge from the concave surface of the kidneys?
Renal blood vessels, nerves, and ureters.
p.25
Nephron Structure and Function
What is the function of the macula densa in the nephron?
It senses NaCl delivery and regulates GFR through paracrine signaling.
p.21
Glomerular Filtration
What is the colloid osmotic pressure gradient (p)?
It is due to proteins in plasma but not in Bowman’s capsule.
p.14
Nephron Structure and Function
What structures are involved in the renal exchange processes?
Collecting duct, distal tubule, afferent arteriole, loop of Henle, efferent arteriole, glomerulus, peritubular capillaries, proximal tubule, and Bowman's capsule.
p.20
Glomerular Filtration
How does the hydrostatic pressure of fluid in Bowman’s capsule affect filtration?
It favors fluid moving back into the glomerular capillaries.
p.13
Nephron Structure and Function
What is Bowman’s capsule?
The structure that encases the glomerulus and collects filtrate.
p.18
Nephron Structure and Function
What is the difference between the afferent and efferent arterioles?
The afferent arteriole brings blood to the glomerulus, while the efferent arteriole carries blood away from it.
What is the pathway of blood flow in the kidney starting from the renal artery?
Renal artery → smaller arteries → arterioles in the cortex → portal system → renal capillaries → interlobular vein → renal vein.
p.7
Nephron Structure and Function
What is the function of the portal system in the kidney?
It includes afferent arterioles, glomerulus, efferent arteriole, peritubular capillaries, and vasa recta.
p.1
Regulation of Plasma Volume and Blood Pressure
How does the urinary system regulate plasma volume and blood pressure?
By controlling the rate at which water is excreted in the urine.
What is the function of the urethra?
To carry urine from the bladder to the outside of the body.
p.22
Glomerular Filtration Rate (GFR)
What does GFR stand for in the urinary system?
Glomerular Filtration Rate.
How do kidneys regulate plasma ion balance?
By balancing dietary intake with urinary loss of key ions.
p.12
Glomerular Filtration
What is the primary function of the glomerulus in the urinary system?
Filtration: blood to lumen.
p.14
Nephron Structure and Function
What is the function of the glomerulus?
It is involved in the filtration of blood to form urine.
p.6
Nephron Structure and Function
Where are cortical nephrons primarily located?
Almost entirely within the cortex.
p.19
Nephron Structure and Function
What is the role of mesangial cells in the glomerulus?
They provide structural support and regulate blood flow within the glomerular capillaries.
p.20
Glomerular Filtration
What is the osmotic pressure gradient in glomerular capillaries?
About 30 mm Hg, favoring fluid moving back into the capillaries.
p.30
Reabsorption and Secretion Processes
What is the function of Na+-K+-ATPase in this process?
It pumps Na+ out of the cell.
p.14
Reabsorption and Secretion Processes
What is excretion in the urinary system?
The process of eliminating substances from the lumen to the external environment.
p.31
Reabsorption and Secretion Processes
How does urea leave the lumen in the proximal tubule?
Through facilitated diffusion transporters into the interstitial fluid.
p.21
Glomerular Filtration
How is net filtration pressure calculated?
Net filtration pressure = P_H - p - P_fluid.
p.9
Nephron Structure and Function
What are the components of the Loop of Henle?
Thin descending limb, thin ascending limb, and thick ascending limb.
p.33
Reabsorption and Secretion Processes
How does the transport rate of glucose change with plasma glucose concentration?
Transport rate is directly proportional to plasma glucose concentration until the transport maximum is reached.
p.10
Nephron Structure and Function
What are macula densa cells responsible for?
Sensing the flow in the distal tubule and releasing paracrine factors that affect the diameter of the afferent arteriole.
p.36
Reabsorption and Secretion Processes
What is the primary function of reabsorption in the urinary system?
To reclaim water and essential solutes from the filtrate back into the bloodstream.
p.10
Nephron Structure and Function
What type of cells are granular cells?
Specialized smooth muscle cells.
p.26
Extrinsic Control of GFR
What happens to GFR and renal blood flow when sympathetic activity increases?
GFR and renal blood flow decrease.
p.38
Micturition and Urination
What is micturition?
The elimination of urine stored in the bladder.
p.26
Extrinsic Control of GFR
What is the function of prostaglandins in the urinary system?
They act as vasodilators and adjust the size of glomerular filtration slits.
p.14
Nephron Structure and Function
What is the purpose of the urinary system?
To eliminate waste materials from the body in the form of urine.
p.21
Nephron Structure and Function
What is the function of the glomerulus?
It filters blood to form urine.
p.31
Reabsorption and Secretion Processes
How does urea move across the epithelium in the proximal tubule?
By diffusion if there is a concentration gradient.
p.30
Reabsorption and Secretion Processes
How does glucose exit the proximal tubule cell?
Glucose diffuses out the basolateral side using the GLUT protein.
p.37
Glomerular Filtration
What is the function of the glomerulus?
It filters blood to form urine.
p.6
Nephron Structure and Function
Why are juxtamedullary nephrons important?
They are crucial for producing concentrated urine during water constraints.
p.22
Glomerular Filtration Rate (GFR)
What blood pressure range allows GFR to stay constant?
Over a wide range of blood pressure, specifically at 90 mmHg.
p.30
Reabsorption and Secretion Processes
What is the relationship between filtrate and interstitial fluid?
Filtrate is similar to interstitial fluid.
p.37
Reabsorption and Secretion Processes
What is secretion in the context of the urinary system?
Movement of substances from blood to lumen.
p.25
Nephron Structure and Function
What is the role of granular cells in the nephron?
They are involved in the regulation of blood pressure and GFR.
p.12
Micturition and Urination
What is excretion in the urinary system?
The elimination of waste products from the body.
p.9
Nephron Structure and Function
What is the renal corpuscle composed of?
Bowman's capsule and the glomerulus.
p.35
Reabsorption and Secretion Processes
What does reabsorption refer to in the nephron?
Transfer from lumen to blood.
p.32
Reabsorption and Secretion Processes
What is the renal threshold?
The plasma concentration at which saturation occurs.
p.32
Reabsorption and Secretion Processes
What is the significance of the transport maximum?
It indicates the rate of transport at saturation.
p.19
Nephron Structure and Function
What is the basal lamina in the urinary system?
An acellular layer of extracellular matrix with negative-charged glycoprotein.
p.30
Reabsorption and Secretion Processes
What type of transporter is SGLT?
Secondary active transporter.
p.23
Intrinsic Control of GFR
What occurs to GFR during a decrease in blood pressure?
The rate decreases and the system may shut down in case of blood loss.
p.28
Reabsorption and Secretion Processes
What drives anion reabsorption in the nephron?
The electrochemical gradient.
Where are the kidneys located in relation to the spine?
On either side of the spine at the level of the eleventh and twelfth ribs.
p.28
Reabsorption and Secretion Processes
How does water move in relation to solute reabsorption?
By osmosis, following solute reabsorption.
p.15
Reabsorption and Secretion Processes
What are peritubular capillaries involved in?
They are involved in the reabsorption and secretion processes.
p.12
Reabsorption and Secretion Processes
What is the role of the collecting duct?
Final reabsorption and secretion before urine is excreted.
p.21
Nephron Structure and Function
What does Bowman’s capsule do?
It collects the filtrate from the glomerulus.
p.14
Reabsorption and Secretion Processes
What does secretion refer to in renal exchange processes?
The movement of substances from the blood to the lumen.
p.31
Reabsorption and Secretion Processes
What happens to water in the proximal tubule that affects urea concentration?
Water moves from the lumen across the epithelium by osmosis, increasing urea concentration in the filtrate.
p.13
Nephron Structure and Function
What is the role of the afferent arteriole in the nephron?
It supplies blood to the glomerulus for filtration.
p.11
Glomerular Filtration
What is the function of the glomerulus in the urinary system?
It facilitates glomerular filtration, allowing protein-free plasma to flow into Bowman’s capsule.
p.21
Glomerular Filtration
What is the fluid pressure (P_fluid) in Bowman’s capsule?
It is the pressure created by the fluid within Bowman’s capsule.
p.18
Reabsorption and Secretion Processes
What is the function of the proximal tubule?
It reabsorbs water, ions, and nutrients from the filtrate back into the blood.
What is the function of the afferent arteriole?
To supply blood to the glomerulus.
p.12
Reabsorption and Secretion Processes
What is secretion in the context of renal function?
Transport of substances from blood into the lumen of the tubule.
Why is the secretion of K+ and H+ important?
It is important in homeostatic regulation of those ions.
p.11
Micturition and Urination
What is the pathway of urine from the kidneys to the external environment?
From the collecting duct to the renal vein, then to the bladder and external environment.
p.25
Reabsorption and Secretion Processes
What is the role of the distal tubule in the nephron?
It is involved in the regulation of potassium and sodium balance.
p.1
Regulation of Plasma Volume and Blood Pressure
What effect does plasma volume have on blood pressure?
Plasma volume exerts a direct effect on blood pressure.
p.24
Regulation of Plasma Volume and Blood Pressure
What initiates the myogenic response in the urinary system?
Stretch of smooth muscle.
p.24
Regulation of Plasma Volume and Blood Pressure
What opens after muscle cell depolarization?
Voltage-gated calcium channels.
p.38
Micturition and Urination
What type of reflex is micturition?
A simple spinal reflex subjected to both conscious and unconscious control from higher brain centers.
p.22
Glomerular Filtration Rate (GFR)
What does the filtration coefficient depend on?
Surface area of the glomerular capillaries and permeability of the interface between the capillary and Bowman’s capsule.
p.37
Nephron Structure and Function
What is the role of the collecting duct in the urinary system?
It collects urine from the distal tubule and transports it to the bladder.
p.38
Micturition and Urination
What happens to the internal sphincter during bladder filling?
It is passively contracted.
p.21
Glomerular Filtration
What is hydrostatic pressure (P_H) in the context of glomerular filtration?
It is the blood pressure that drives filtration.
p.17
Glomerular Filtration
What happens to the remaining four-fifths of plasma flow?
It flows into peritubular capillaries along with plasma proteins and blood cells.
p.20
Glomerular Filtration
What is the effect of hydrostatic pressure of blood on glomerular filtration?
It favors filtration into Bowman’s capsule.
p.27
Reabsorption and Secretion Processes
What is the difference between filtration and reabsorption in the urinary system?
Filtration is the movement of blood to lumen, while reabsorption is the movement from lumen to blood.
p.12
Glomerular Filtration Rate (GFR)
What is the significance of the afferent and efferent arterioles?
They regulate blood flow into and out of the glomerulus.
p.38
Micturition and Urination
What is the state of the bladder when it is at rest?
It is in a relaxed (filling) state with tonic discharge.
p.9
Nephron Structure and Function
What is the role of the distal tubule in the nephron?
It is involved in the final adjustments of urine composition.
p.11
Glomerular Filtration
What is the role of the efferent arteriole?
It carries blood away from the glomerulus after filtration.
p.8
Nephron Structure and Function
What is the glomerulus?
A ball-like network of capillaries.
p.7
Nephron Structure and Function
What is the glomerulus?
A ball-like network of capillaries in the kidney.
p.10
Nephron Structure and Function
What do granular cells secrete?
Renin, to regulate salt and water balance.
p.7
Nephron Structure and Function
What is the role of the vasa recta?
It is the first set of capillaries in the medulla.
p.29
Reabsorption and Secretion Processes
What happens to sodium (Na+) at the basolateral side of the proximal tubule cell?
It is actively pumped out by the Na+ - K+ - ATPase.
How does the urinary system regulate plasma pH?
By regulating bicarbonate and hydrogen ions in the plasma.
p.20
Glomerular Filtration
What are the three pressures that influence glomerular filtration?
Hydrostatic pressure of blood, colloid osmotic pressure, and hydrostatic pressure of fluid in Bowman’s capsule.
Which key ions do the kidneys help to balance?
Sodium (Na+), potassium (K+), and calcium (Ca2+).
p.13
Reabsorption and Secretion Processes
What is secretion in the context of renal function?
The transport of molecules from the plasma of peritubular capillaries to the lumen of renal tubules.
p.28
Reabsorption and Secretion Processes
What is the relationship between filtrate and interstitial fluid?
Filtrate is similar to interstitial fluid.
p.18
Glomerular Filtration
What is the role of podocytes in the filtration process?
They form filtration slits that help regulate the passage of substances into Bowman’s capsule.
p.25
Regulation of Plasma Volume and Blood Pressure
How does the afferent arteriole respond to increased GFR?
It constricts to increase resistance and decrease GFR.
p.38
Micturition and Urination
What is the role of higher CNS input in micturition?
It may facilitate or inhibit the reflex.
p.21
Glomerular Filtration
What factors affect glomerular filtration?
Blood pressure, surface area, pore size, and slit size.
p.25
Nephron Structure and Function
What is the role of the collecting duct in the nephron?
It is involved in the final concentration of urine.
p.35
Glomerular Filtration
What is the function of the glomerulus?
Filtration of blood to the lumen.
p.34
Reabsorption and Secretion Processes
What is the renal threshold?
The plasma concentration at which a solute first appears in the urine.
p.16
Osmolarity Regulation
What is the relationship between hydration and solute concentration in the nephron?
Increased hydration leads to lower solute concentration in the filtrate.
p.33
Reabsorption and Secretion Processes
What type of graph represents the relationship between transport rate and plasma glucose concentration?
A linear graph until the transport maximum is reached.
p.8
Nephron Structure and Function
What are the peritubular capillaries?
Capillaries that surround the tubule.
p.19
Nephron Structure and Function
What type of proteins are found on the surface of the endothelium in the urinary system?
Negative-charged proteins.
p.5
Micturition and Urination
What is the function of the ureter in the urinary system?
To transport urine from the renal pelvis to the bladder.
How is osmolarity regulated in the body?
By tightly controlling the rate of water reabsorption in relation to solute concentration.
p.19
Nephron Structure and Function
What are podocytes?
Modified epithelial cells in the urinary system.
p.15
Nephron Structure and Function
What is the function of the efferent arteriole?
It carries blood away from the glomerulus after filtration.
p.13
Glomerular Filtration
What is the process of glomerular filtration?
The movement of blood to the lumen of the renal tubules.
p.36
Regulation of Plasma Volume and Blood Pressure
How does the body regulate the reabsorption of water?
Through hormones like antidiuretic hormone (ADH).
p.15
Nephron Structure and Function
What is the pathway of solute after filtration?
From the glomerulus to Bowman's capsule, then to the tubule, and finally to the renal vein and bladder.
p.12
Reabsorption and Secretion Processes
What is the function of the distal tubule?
Reabsorption and secretion of ions and water.
p.13
Micturition and Urination
What is the pathway of excretion in the urinary system?
From the collecting duct to the bladder and then to the external environment.
p.37
Reabsorption and Secretion Processes
What is the process of filtration in the urinary system?
Movement of substances from blood to lumen.
p.12
Micturition and Urination
What is the pathway of urine from the kidneys to the external environment?
From the collecting duct to the renal vein, then to the bladder and external environment.
p.13
Nephron Structure and Function
What is the function of the loop of Henle?
It plays a crucial role in the concentration of urine.
p.11
Glomerular Filtration
What is the role of Bowman’s capsule?
It collects the filtrate from the glomerulus.
p.35
Reabsorption and Secretion Processes
What does secretion depend on?
Membrane transport systems.
p.13
Reabsorption and Secretion Processes
What happens to the filtered blood after passing through the renal tubules?
It is either reabsorbed into the blood or excreted as urine.
p.18
Glomerular Filtration
What is glomerular filtration?
The process by which substances leave the plasma and enter the tubule lumen through filtration barriers.
p.18
Glomerular Filtration
What is the significance of the basal lamina in the filtration process?
It acts as a selective barrier that prevents large molecules from passing into the filtrate.
p.25
Reabsorption and Secretion Processes
What is the function of the proximal tubule?
It is responsible for the reabsorption of water, ions, and nutrients.
p.11
Nephron Structure and Function
What is the proximal tubule's primary function?
It reabsorbs the majority of filtered water, ions, and nutrients.
p.17
Glomerular Filtration
What remains in the capillary during glomerular filtration?
Blood cells and plasma proteins.
p.18
Glomerular Filtration
What are the three filtration barriers in the renal corpuscle?
1. Glomerular capillary endothelium, 2. Basal lamina, 3. Epithelium of Bowman’s capsule.
p.20
Glomerular Filtration
What is the hydrostatic pressure of fluid in Bowman’s capsule?
About 15 mm Hg, favoring fluid moving back into the glomerular capillaries.
p.30
Reabsorption and Secretion Processes
What substances are reabsorbed in the proximal tubule?
Glucose, amino acids, ions, and organic molecules.
p.17
Glomerular Filtration
What is the filtration fraction?
The percentage of total plasma volume that filters into the tubule.
p.35
Reabsorption and Secretion Processes
What is secretion in the context of the urinary system?
Transfer of molecules from extracellular fluid into the lumen of the nephron.
p.27
Nephron Structure and Function
What happens to the filtrate after passing through the distal tubule?
It moves to the collecting duct and then to the renal vein or bladder.
What is the role of peritubular capillaries in the nephron?
To facilitate the exchange of substances between blood and the nephron.
p.35
Reabsorption and Secretion Processes
What is the result of secretion in the nephron?
An increase in the quantity of solute excreted in the urine.
p.11
Nephron Structure and Function
What are peritubular capillaries?
They surround the nephron and are involved in reabsorption and secretion.
p.15
Reabsorption and Secretion Processes
What is the relationship between the amount of solute filtered, reabsorbed, and secreted?
Amount excreted = Amount filtered - Amount reabsorbed + Amount secreted.
p.6
Nephron Structure and Function
What role do both types of nephrons play?
Both are involved in urine formation.
p.37
Reabsorption and Secretion Processes
What does reabsorption refer to in the urinary system?
Movement of substances from lumen to blood.
p.12
Reabsorption and Secretion Processes
What is the function of the loop of Henle?
Concentration of urine through reabsorption of water and salts.
p.9
Nephron Structure and Function
What is the flow sequence of filtered fluid in the nephron?
Renal corpuscle → Proximal tubule → Loop of Henle → Distal tubule → Collecting duct → Renal pelvis → Ureter.
p.37
Micturition and Urination
What is excretion in the urinary system?
Movement of substances from lumen to external environment.
p.11
Reabsorption and Secretion Processes
What is the process of secretion in the kidneys?
It involves the transfer of substances from the blood into the tubular lumen.
p.11
Reabsorption and Secretion Processes
What is excretion in the context of the urinary system?
The elimination of waste products from the body through urine.
p.25
Nephron Structure and Function
What is the significance of the Loop of Henle in the nephron?
It plays a crucial role in concentrating urine and maintaining osmolarity.
p.35
Micturition and Urination
What is the pathway of urine from the nephron to the external environment?
From the nephron to the renal vein, then to the bladder and external environment.
p.38
Micturition and Urination
What occurs when stretch receptors in the bladder fire?
Parasympathetic neurons fire, motor neurons stop firing, and smooth muscle contracts.
p.27
Nephron Structure and Function
What is the function of the loop of Henle?
To concentrate urine and facilitate the reabsorption of water and solutes.
p.14
Micturition and Urination
What is the pathway of urine from the nephron to the external environment?
From the collecting duct to the renal vein, then to the bladder and external environment.
p.11
Reabsorption and Secretion Processes
What occurs during reabsorption in the renal system?
Substances are transported from the lumen back into the blood.
p.25
Nephron Structure and Function
What structures are involved in the juxtaglomerular apparatus?
Macula densa, afferent arteriole, and granular cells.
p.18
Glomerular Filtration
What are filtration slits?
Narrow gaps between the foot processes of podocytes that allow filtered material to pass into Bowman’s capsule.
p.11
Nephron Structure and Function
What is the Loop of Henle's function?
It plays a crucial role in the concentration of urine.
Why is a high blood flow rate critical for renal function?
It is essential for the kidneys to perform their functions effectively.
p.9
Nephron Structure and Function
What is the significance of the nephron's configuration?
It can sense fluid flow in the proximal tubule.
p.11
Glomerular Filtration
What is the function of the afferent arteriole?
It supplies blood to the glomerulus for filtration.
p.11
Nephron Structure and Function
What is the distal tubule's role in the nephron?
It is involved in the reabsorption of sodium and water, and secretion of potassium and hydrogen.
p.9
Nephron Structure and Function
What is the function of the collecting duct?
To collect urine from multiple nephrons and transport it to the renal pelvis.
p.35
Nephron Structure and Function
What is the role of the collecting duct in the nephron?
It is involved in the final concentration of urine.
