Chapter 20 Flashcards
The kidneys are located in the ? Space
Retroperitoneal
The entrance into the kidney is called the ?
Hilum
Which structure is the first to collect the urine?
Calyx
The calyces (calyx) are the extensions of the pelvis that receive the urine that has been formed
Each minor calyx receives urine from the ?
Renal papilla
Renal papilla is the rounded surface at the apex of each pyramid
Which blood vessel conveys blood out of the nephron
Interlobular vein.
Blood is not considered to be completely out of the nephron until it enters a vein.
Which blood vessels surround the loops of Henle?
Vasa recta
Vasa recta are branches of the periubular capillaries that dip into the medulla to encircle the loops
Which process is most affected by blood pressure?
Glomerular filtration
Blood pressure creates a sufficiently high hydrostatic pressure within the glomeruli to overcome the osmotic forces in the blood
Name 3 things found in the glomerular filtrate
Glucose, Uric acid and creatinine
What muscle metabolism waste product is eliminated by the kidneys
Creatinine
Renal secretion of a compound usually occurs from the ? Into the distal convoluted tubule?
Peritubular capillaries
Name 3 things usually secreted by the kidneys?
Creatinine, H+, penicillin
Creatine is reabsorbed under renal threshold limit rules, creatinine is not reused.
The compound used to assess the function of the kidney at the level of the glomerulus is
Inulin
Inulin is a polysaccharide that is cleared from the blood totally by filtration at the glomerulus, creatinine is secreted.
What could appear in the urine from dieting or the utilization of excess lipids
Ketone
Ketones are usually acidic end products of lipid catabolism and may result from dietary or disease causes
Vigorous exercise could release high amounts of ? Into the urine
Albumin
Albumin is the most common blood protien and could spill into the urine if high blood pressure forced it through the glomerular capillaries which are normally not permeable to colloids
What causes urine to flow from the kidneys to the bladder
Peristalsis
The ureters have smooth muscle which causes peristaltic waves to move the urine
Juxtaglomerular cells of the juxtaglomerular apparatus secrete ? When ?
Renin when blood pressure drops
Low blood pressure or low tubular osmotic pressure triggers activation of the renin-angiotensin system
Tubular reabsorption is responsible for retaining nutrients the body requires. Most tubular reabsorption occurs in the ? Where microvilli and their numerous carrier protiens increase the surface area available for reabsorption
Proximal convoluted tubule
70% or more of all reabsorption occurs in the initial segment of the renal tubule
Why is the plant compound known as inulin the best substance to use to measure renal clearance?
Inulin is neither reabsorbed nor actively secreted into the filtrate
In males as well as females, the external urethral sphincter is made up of skeletal muscles and thus is under voluntary control. Where is the external urethral sphincter located in males?
Within the urogenital diaphragm
The external urethral sphincter is part of the pelvis
What structure is last in the sequence of urine flow
Medulla
The medulla is the middle layer of the kidneys that contain the pyramids and columns
The striated appearance of the pyramids is caused by
Microtubules
The kidney contains millions of micro tubules that run parallel to each other within the pyramids
The kidney secretes ? For the purpose of stimulating bone marrow activity
Erythropoietin
Name 3 functions of the renal system
Maintain blood pH
Regulate blood pressure
Control blood concentration
The kidneys filter the blood and control its concentration of electrolytes, pH, water, wastes and carbon dioxide
How much of the cardiac output passes through the kidneys
25%
From 15-35% of the total blood of the cardiac output filters through the kidneys
What blood vessel delivers blood to the cortex
Interlobular artery
The interlobular arteries enter the cortex from the interlobar arteries and give off branches that surround the renal corpuscles
The renal corpuscle is comprised of a glomerulus and ?
Bowman’s capsule
The glomerulus and glomerular capsule are considered a functional unit called the renal corpuscle
What section of the nephron is after the ascending limb of the loop of Henle
Distal convoluted tubule
The last part of the nephron is the
Collecting duct
The collecting ducts receive the distal convoluted tubules from several nephrons
What area actually secretes renin into the blood
Juxtaglomerular cells
The juxtaglomerular cells are within the affferent arteriole
What has the highest concentration in the urine
Sodium
What ion is reabsorbed in exchange for sodium
Potassium
Because of the sodium-potassium membrane pump, potassium always moves in the opposite direction to sodium
What is the average glomerular filtration rate
180L per day
The kidneys can filter up to 125 ml per minute or 180L per day
What is usually not found in urine
Glucose
How much urine is formed in 24 hours
1.5 L
On average, persons produce between .6 and 2.5 liters of urine daily
Renin acts on ? To convert it to angiotensin I
Angiotensinogen
The targets of angiotensin II are blood vessels and
Adrenal cortex
Angiotensin II causes vasoconstriction and the release of aldosterone from the adrenal cortex
Tubular reabsorption occurs from the nephron tubules into the
Periubular capillaries
Most tubule reabsorption occurs at the
Proximal convoluted tubule
The microvilli form a brush border on the epithelial cells in the proximal tubule that effectively increase its surface area for permeability
Name 3 things that operate under a renal threshold mechanism
Creatine, ascorbic acid and citric acid
The action of aldosterone is to increase
Sodium reabsorption
Aldosterone acts on the distal convoluted tubule to reabsorbed and conserve sodium blood levels
How much sodium is actively reabsorbed by the proximal segment if the nephron
70%
About 70% of the sodium that will be reabsorbed will occur at e proximal tubule
The countercurrent multiplier mechanism occurs at the
Loop of Henle
The fluid in the descending limb of the loop of Henle is ? Relative to the capillaries
Hypertonic
The fluid in the descending limb is hypertonic while the ascending limb is hypotonic
The function of the countercurrent multiplier is to
Increase the concentration of NaCl
The purpose of e loop of Henle is to produce a NaCl concentration beyond what could be expected under normal physiologic rules of transport
What affect does ADH have on urine output
Decreases
Anti diuretic hormone from the posterior pituitary and hypothalamus causes the kidney to reabsorb water and reduce diuresis
Where does ADH have its greatest effect
Distal convoluted tubule
ADH causes the distal convoluted tubule and the surrounding capillaries to increase their permeability to water so that it can be facultatively reabsorbed (on demand)
Eating large amounts of meat will increase the level of ? In the blood
Urea
Proteins are catabolized into urea
Renal calculi are comprised of what 3 things
Calcium oxalate, Uric acid and magnesium phosphate
Kidney stones do not contain cholesterol, but mainly oxalate. Cholesterol is usually found in gallbladder stones (cholelithiases)
The mucosa of the bladder is comprised of
Transitional epithelium
The lining of the bladder can be distended without tearing the protective coating of the mucous layer
What renal muscle is under voluntary control
External urethral sphincter
The micturition reflex is centered in the
Sacral cord
Make 3 statements that characterize the kidneys
The kidneys are positioned retroperitoneally
The kidney is padded by a layer of fat
Inside the kidney is a hollow camber called the renal sinus
The granular appearance of the renal cortex is due to?
The random distribution of nephrons in this area
The final branches of the interlobular arteries give rise to the ?
Afferent arterioles
Afferent arterioles branch off the interlobular arteries
The concentration of substances in the plasma, in the glomerular filtrate and in urine differ in what way
Plasma and glomerular filtrate are virtually indentical, but urine contains proportionately more waste products
What force favors filtration
Glomerular hydrostatic pressure
Glomerular blood (hydrostatic) pressure is the outward force of filtration
Name 3 factors that affect glomerular filtration rates
Blood pressure
Osmotic pressure of the glomerular filtrate
Plasma osmotic pressure
The outermost structure of a kidney is the
Capsule
The kidney is surrounded by a capsule of dense irregular CT
What is the main factor that causes urine to enter the urinary bladder
Peristalsis
Peristalsis of the ureter moves urine from the renal pelvis to the bladder. Internal surface tension prevents gravity from playing a role
What is the main factor that promotes bladder infections in a female
Length of the urethra
The relatively short urethra makes bacterial entry into the bladder much more likely than in males
The urinary system functions to excrete
Soluble nitrogenous wastes
The structure which receives the filtrate from the glomerulus is the
Bowman’s capsule
The enlarged end of the renal tubule that surrounds the glomerulus is called the bowman’s capsule
In which area can the term urine be correctly used
Minor calyx
Once filtrate exits the collecting duct it can no longer be processed, and thus is urine
The kidneys have the capability of controlling their own blood flow independent of general controls for circulation of organs such a s the pancreas
T or F
True
the kidney, brain, and skeletal muscle have a high demand for oxygen and have internal mechanisms for autoregulation
The reason that most people only have trace amounts of albumin in their urine is that it is returned to the blood by reabsorption
T or F
False
Albumin is a protein which is not filtered through the glomerulus and therefore cannot cross its capillaries
The appearance of glycosuria indicates that the renal plasma threshold has been exceeded
T or F
True
The appearance of sugar in the urine indicates that the level in the blood exceeds the ability of the kidneys to reabsorb all of it
Vitamin C will appear in the urine when an excess is consumed in the diet or supplements
True
Vitamin C is reabsorbed into the blood at the proximal consulted tubule but only to a specific limit, taking large diesels of vitamin C will cause elimination of most of it in the urine
The nephrotic syndrome usually causes hypoproteinemia, proteinuria and generalized edema
T or F
True
The nephrotic syndrome is renal damage that occurs in several diseases and causes loss of protiens into the urine
Ions such as chloride usually passively follow the movement of cations to achieve electrical balance
T or F
True
Cell membrane are charged and their ionic potentials must be maintained at homeostatic levels; Cl- can follow Na+ to balance the loss of a positive charge
Water will move from a hypotonic to a hypertonic area by osmosis
T or F
True
Osmosis is governed by the concentrations of water and solute; the greater solute concentration (hypertonic) will have the least amount of water; water moves from high water (hypotonic) to lower water (hypertonic) concentrations
An increase of ADH production will tend to make the blood more hypertonic
T or F
False
The effect of ADH on water retention dilutes the blood making it more hypotonic
Excessive sweating will usually cause a person to withhold their secretion of ADH
T or F
False
Loss of water during sweating usually causes the secretion of ADH to help conserve water and blood tonicity
Aldosterone and ADH tend to have the same effect of blood concentration
T or F
False
ADH tends to cause blood to be hypotonic while aldosterone conserves salt and makes the blood hypertonic; both act together to maintain homeostasis
Gout is a diseas that causes Uric acid crystals to form in joints
T of F
True
Gout is a metabolic disorder that causes excess Uric acid in the blood to precipitate in and around joints and other tissues
The secretion of H+ and reabsorption of bicarbonate anions are important pH regulating mechanisms of the kidney
T or F
True
The kidney normally retains bicarbonate and secretes H+ to maintain pH balance by buffering mechanisms
PAH is a plasma clearance test that can be used to assess plasma flow through. The kidneys.
T or F
True
Para-aminohippuric acid is filtered at the glomerulus and secreted; PAH along with hematocrit can be used to assess total blood through the kidneys
Infants have a greater probability of dehydrating than adults
T or F
True
The kidneys are immature in children and do not have the ability to conserve water that they will have as adults; children could dehydrate from excess urination
Cystitis could spread from the bladder to the kidneys through the urethra.
T or F
False
The ureter is the tube which connects the bladder to the pelvis of the kidney
The membrane urethra is the portion found in males as well as females
T or F
True
The membranous urethra is located in the urogenital diaphragm at the floor of e pelvic cavity; there is no female analog to the prostrate
In the female, the urinary bladder lies posterior to the uterus and vagina
T orF
False
E urinary bladder is the most anterior pelvic structure in males and females
It is normal for urine and semen to mix in the male
T or F
False
The internal urethral sphincter contracts blocking the bladder during male sexual arousal
The internal urethral sphincter is totally under parasympathetic, autonomic control
T or F
False
The autonomic nervous system controls smooth muscle
Persons with spinal cord damage in the lumbar area no longer have urination reflexes
T or F
False
Sacral cord controls these reflexes, and therefore they would still occur, however conscious awareness of the reflexes would be lost
Chronic glomerulonephritis is usually a renal infection associated with streptococcal bacteria
T or F
False
Acute glomerulonephritis is normally associated with streptococcal infection; chronic glomerulonephritis may be non-infectious in nature
The glomerulus most closely resembles an area of capillaries
T or F
True
The glomerulus is a ball of capillaries intermixed with specialized connective and epithelial cells
There are about 1million nephrons in each kidney
T or F
True
