Chapter 25-Urinary System
How might the contents of the filtrate be altered if the filtration membrane is damaged or destroyed?
-Increase protein producing a condition called proteinuria AND -Presence of blood cells can occur, depending on the amount of damage. This condition is called hematuria.
The basic functions of the nephrons are which of the following: 1. osmosis, 2. filtration, 3. diffusion, 4. secretion, 5. reabsorption
2, 4, and 5 are correct filtration, secretion, and reabsorption
Place the following in correct sequence from the formation of a drop of urine to its elimination from the body. 1. major calyx 2. minor calyx 3. nephron 4. urethra 5. ureter 6. collecting duct
3, 6, 2, 1, 5, 4 nephron, collecting duct, minor calyx, major calyx, ureter, urethra
Passive Transport
A process that does not require cellular energy to transport substance across the cell membrane.
The renal corpuscle is made up of ________. A) Bowman's capsule and glomerulus B) the renal papilla C) the descending loop of Henle D) the renal pyramid
A) Bowman's capsule and glomerulus
The function of angiotensin II is to ________. A) constrict arterioles and increase blood pressure B) decrease the production of aldosterone C) decrease arterial blood pressure D) decrease water absorption
A) constrict arterioles and increase blood pressure
Which of the following is not reabsorbed by the proximal convoluted tubule? A) creatinine B) Na+ C) glucose D) K+
A) creatinine
The mechanism that establishes the medullary osmotic gradient depends most on the permeability properties of the ________. A) nephron loop B) glomerular filtration membrane C) collecting duct D) distal convoluted tubule
A) nephron loop
An individual is severely dehydrated. How would this affect their ADH release and the volume of their urine?
ADH release would increase and urine volume would decrease -ADH causes the kidney to reabsorb more water, minimizing water loss from the body.
Which of the following hormones acting on the collecting duct is most responsible for retaining Na+ ions in the body?
Aldosterone
Toxins, drugs, and metabolic wastes are cleared from the body by secretion into the filtrate. Which parts of the nephron could these items be secreted into?
Any part of the nephron except the nephron loop -Secretion of substances takes place in the proximal and distal tubule, and in the collecting duct.
Tight Junction
Area where plasma membranes of adjacent cells are tightly bound together, forming an impermeable barrier.
An important characteristic of urine is its specific gravity or density, which is ________. A) 1.000-1.015 B) 1.001-1.035 C) 1.041-1.073 D) 1.030-1.040
B) 1.001-1.035
Which of the hormones below is responsible for facultative water reabsorption? A) aldosterone B) ADH C) atrial natriuretic peptide D) thyroxine
B) ADH
What would happen if the capsular hydrostatic pressure were increased above normal? A) Net filtration would increase above normal. B) Net filtration would decrease. C) Filtration would increase in proportion to the increase in capsular pressure. D) Capsular osmotic pressure would compensate so that filtration would not change.
B) Net filtration would decrease
Which of the choices below is a function of the nephron loop? A) form a large volume of very concentrated urine or a small volume of very dilute urine B) form a large volume of very dilute urine or a small volume of very concentrated urine C) absorb electrolytes actively and water by osmosis in the same segments D) absorb water and electrolytes into the tubular network
B) form a large volume of very dilute urine or a small volume
Which of the choices below is a function of the loop of Henle? A) form a large volume of very concentrated urine or a small volume of very dilute urine B) form a large volume of very dilute urine or a small volume of very concentrated urine C) absorb electrolytes actively with an automatic absorption of water by osmosis D) none of these
B) form a large volume of very dilute urine or a small volume of very concentrated urine
The factor favoring filtrate formation at the glomerulus is the ________. A) colloid osmotic pressure of the blood B) glomerular hydrostatic pressure C) capsular hydrostatic pressure D) myogenic mechanism
B) glomerular hydrostatic pressure
What is the most direct function of the juxtaglomerular apparatus? A) help regulate blood pressure and the rate of blood filtration by the kidneys B) help regulate blood pressure and the rate of excretion by the kidneys C) help regulate urea absorption by the kidneys D) help regulate water and electrolyte excretion by the kidneys
B) help regulate blood pressure and the rate of excretion by the kidneys
Excretion of dilute urine requires ________. A) relative permeability of the distal tubule to water B) impermeability of the collecting tubule to water C) transport of sodium and chloride ions out of the descending loop of Henle D) the presence of ADH
B) impermeability of the collecting tubule to water
The mechanism of water reabsorption by the renal tubules is ________. A) active transport B) osmosis C) filtration D) cotransport with sodium ions
B) osmosis
If one says that the clearance value of glucose is zero, what does this mean? A) The glucose molecule is too large to be filtered out of the blood. B) Most of the glucose is filtered out of the blood and is not reabsorbed in the convoluted tubules. C) Normally all the glucose is reabsorbed. D) The clearance value of glucose is relatively high in a healthy adult.
C) Normally all the glucose is reabsorbed.
Which of the following is not associated with the renal corpuscle? A) an efferent arteriole B) a fenestrated capillary C) a vasa recta D) a podocyte
C) a vasa recta
Which of the choices below are the most important hormone regulators of electrolyte reabsorption and secretion? A) angiotensin II and ADH B) angiotensin I and epinephrine C) angiotensin II and aldosterone D) angiotensin I and atrial natriuretic peptide
C) angiotensin II (stimulates reabsorption of Na+) and aldosterone (promotes synthesis of Na+/K+ channels and pumps)
The kidneys are stimulated to produce renin ________. A) when the peritubular capillaries are dilated B) when the pH of the urine decreases C) by a decrease in the blood pressure D) when the specific gravity of urine rises above 1.10
C) by a decrease in the blood pressure
Which of the choices below is not a glomerular filtration rate control method? A) renal autoregulation B) neural regulation C) electrolyte levels D) hormonal regulation
C) electrolyte levels
The chief force pushing water and solutes out of the blood across the filtration membrane is ________. A) the design and size of the podocytes B) the thickness of the capillary endothelium C) glomerular hydrostatic pressure (glomerular blood pressure) D) the size of the pores in the basement membrane of the capillaries
C) glomerular hydrostatic pressure (glomerular blood pressure)
What is the function of the juxtaglomerular apparatus? A) help regulate water and electrolyte excretion by the kidneys B) help regulate blood pressure and the rate of excretion by the kidneys C) help regulate blood pressure and the rate of blood filtration by the kidneys D) help regulate urea absorption by the kidneys
C) help regulate blood pressure and the rate of blood filtration by the kidneys
Most electrolyte reabsorption by the renal tubules is ________. A) not limited by a transport maximum B) in the distal convoluted tubule C) hormonally controlled in distal tubule segments D) accomplished after the nephron loop is reached
C) hormonally controlled in distal tubule segments
Alcohol acts as a diuretic because it ________. A) is not reabsorbed by the tubule cells B) increases the rate of glomerular filtration C) inhibits the release of ADH D) increases secretion of ADH
C) inhibits the release of ADH
Which of the choices below is the salt level-monitoring part of the nephron? A) loop of Henle B) principal cell C) macula densa D) vasa recta
C) macula densa
The juxtaglomerular apparatus is responsible for ________. A) the secretion of acids and ammonia B) reabsorption of organic molecules, vitamins, and water C) regulating the rate of filtrate formation and controlling systemic blood pressure D) the secretion of drugs
C) regulating the rate of filtrate formation and controlling systemic blood pressure
Which of the choices below is the least important role of tubular secretion? A) disposing of substances not already in the filtrate, such as certain drugs B) eliminating undesirable substances such as urea and uric acid that have been reabsorbed by passive processes C) ridding the body of bicarbonate ions D) ridding the body of excessive potassium ions
C) ridding the body of bicarbonate ions
Which of the following is not true regarding tubular reabsorption? A) It occurs via transcellular or paracellular routes B) It is a reclamation process C) It involves hormonal signals in the collecting ducts D) It is a purely passive transport process.
D) It is a purely passive transport process
Which of the following does not describe the juxtaglomerular complex? A) It regulates the rate of filtrate formation. B) It helps control systemic blood pressure C) Its granular cells produce rennin D) Its macula densa cells produce aldosterone
D) Its macula densa cells produce aldosterone
Which of the choices below does not describe the importance of tubular secretion? A) Disposing of substances not already in the filtrate, such as certain drugs B) Ridding the body of excessive potassium ions C) Eliminating undesirable substances such as urea and uric acid that have been reabsorbed by passive processes D) Ridding the body of bicarbonate ions
D) Ridding the body of bicarbonate ions
Which of the following hormones acting on the collecting duct is most responsible for retaining sodium ions in the blood? A) antidiuretic hormone B) parathyroid hormone C) atrial natriuretic peptide D) aldosterone
D) aldosterone
Which of the choices below is not a method by which the cells of the renal tubules can raise blood pH? A) by secreting hydrogen ions into the filtrate B) by reabsorbing filtered bicarbonate ions C) by producing new bicarbonate ions D) by secreting sodium ions
D) by secreting sodium ions
The macula densa cells respond to ________. A) aldosterone B) antidiuretic hormone C) changes in pressure in the tubule D) changes in solute content of the filtrate
D) changes in solute content of the filtrate
The descending limb of the nephron loop ________. A) is not permeable to water B) is freely permeable to sodium and urea C) pulls water by osmosis into the lumen of the tubule D) contains fluid that becomes more concentrated as it moves down into the medulla
D) contains fluid that becomes more concentrated as it moves down into the medulla
Which of the choices below is not a function of the urinary system? A) helps maintain homeostasis by controlling the composition, volume, and pressure of blood B) regulates blood glucose levels and produces hormones C) maintains blood osmolality D) eliminates solid, undigested wastes and excretes carbon dioxide, water, salts, and heat
D) eliminates solid, undigested wastes and excretes carbon dioxide, water, salts, and heat
Osmosis
Diffusion of a solvent through a selectively permeable membrane from a dilute solution to a more concentrated one.
(T/F) An excessive urine output is called anuria.
False
(T/F) Angiotensin II is a substance made by the body to lower blood pressure during stress.
False
(T/F) Blood pressure in the renal glomerulus is lower than in most parts of the body in order to conserve body water.
False
(T/F) Both the male and female urethras serve the urinary and the reproductive systems
False
(T/F) Fetal kidneys have the primary responsibility of clearing wastes from the fetal blood.
False
(T/F) Glomerular filtration is an ATP-driven process.
False
(T/F) If the GFR is too low, needed substances may pass so quickly through the renal tubules that they are not absorbed and instead are lost in the urine.
False
(T/F) The collecting duct is impermeable to water in the presence of ADH.
False
(T/F) The descending limb of the loop of Henle is permeable to both solutes and water.
False
(T/F) The kidney consumes about 15% of all oxygen used by the body at rest.
False
(T/F) The macula densa cells are chemoreceptors that respond to changes in the urea content of the filtrate.
False
(T/F) The path urine takes after it is formed until it leaves the body is the urethra, urinary bladder, and finally the ureter.
False
(T/F) The proximal convoluted tubule is the portion of the nephron that attaches to the collecting duct
False
(T/F) The trigone is so named because of the shape of the urinary bladder
False
(T/F) Urea is reabsorbed in the nephron loop.
False
(T/F)The proximal convoluted tubule is the portion of the nephron that attached to the collecting duct.
False
(T/F) Having a kinked ureter is called renal ptosis
False. Renal ptosis, a condition in which the kidneys drift below their normal position
(T/F) The myogenic mechanism reflects the tendency of vascular smooth muscle to stretch.
False.The myogenic mechanism is how arteries and arterioles react to an increase or decrease of blood pressure to keep the blood flow constant within the blood vessel. Myogenic response refers to a contraction initiated by the myocyte itself instead of an outside occurrence or stimulus such as nerve innervation.
In the juxtaglomerular complex, what cells monitor and respond to changes in the NaCl concentration in the renal filtrate?
Macula densa cells
Facilitated Diffusion
Passive transport process used by certain large or charged molecules (e.g., Na+, glucose) that are unable to cross through the plasma membrane unaided. Involves movement through channels or movement facilitated by a transport protein.
The majority of reabsorption of water and solutes from the filtrate takes place in which part of the renal tubule?
Proximal tubule -As much as 70% of the water and solutes are reabsorbed into the blood at the proximal tubule.
During reabsorption, what causes water to move from renal tubules into the interstitial space around the peritubular capillaries?
Sodium is transported from the tubule cell to the interstitial space, and water follows by osmosis. -The pumping of sodium ions from the tubular cell to the interstitial space increases the osmolarity of the interstitial space and water follows by osmosis.
If the diameter of the efferent arterioles leading away from the glomerulus decrease (vasoconstriction) which of the following is not likely to occur?
Systemic BP (blood pressure) will go up
Primary Active Transport
The active transport process in which the energy liberated from ATP is transferred directly to the carrier molecule participating in the transport.
Osmolarity
The number of solute particles present in one liter of a solution.
Select the correct statement about the nephron
The parietal Layer of the glomerular capsule is simple squamous epithelium.
Glomerular Filtration
The process by which the glomerulus filters water and solutes from the blood.
Secondary Active Transport
The transport process that uses the energy of one substance moving down its concentration gradient to transport another substance against its concentration gradient across the membrane. The driving concentration gradient is created by primary active transport. Also called cotransport.
Simple Diffusion
The unassisted transport across a plasma membrane of a lipid-soluble or very small particle.
(T/F) Aldosterone is a hormone that causes the renal tubules to reclaim sodium ions from the filtrate.
True
(T/F) Blood in the urine may be a symptom of bladder cancer
True
(T/F) In the absence of hormones, the distal tubule and collecting ducts are relatively impermeable to water
True
(T/F) Incontinence is the inability to control voluntary micturition.
True
(T/F) Obligatory water reabsorption involves the movement of water along an osmotic gradient.
True
(T/F) The act of emptying the bladder is called voiding
True
(T/F) The entire responsibility for urine formation lies with the nephron.
True
(T/F) The urethra contains an internal sphincter of smooth muscle
True
(T/F) Tubular secretion is effective in controlling blood pH.
True
(T/F) Water reabsorption through the proximal convoluted tubule is termed obligatory water reabsorption, whereas water reabsorption through the distal convoluted tubule is termed facultative water reabsorption
True
(T/F)In the absence of hormones, the distal tubule and collecting ducts are relatively impermeable to water.
True
(T/F)T he position of the kidneys behind the peritoneal lining of the abdominal cavity is described by the term retroperitoneal
True
(T/F)The entire responsibility of urine formation lies with the nephron.
True
(T/F)The urethra contains an internal sphincter of smooth muscle.
True
In the kidneys, the countercurrent mechanism involves the interaction between the flow of filtrate through the loop of Henle of the juxtamedullary nephrons (the countercurrent multiplier)and the flow of blood through the limbs of adjacent blood vessels (the countercurrent exchanger). This relationship establishes and maintains an osmotic gradient extending from the cortex through the depths of the medulla that allows the kidneys to vary urine concentration dramatically.
True
(T/F) Atrial natriuretic peptide inhibits sodium reabsorption.
True. Is secreted by the heat in response to stretching of atria(by raising bp). The kidney inhibits sodium ion reabsorption and renin release. The adrenal cortex inhibit secretion of aldosterone and decreases bp.
Which of the following substances is not found in normal renal filtrate?
blood cells and macromolecules
Some drugs and waste products do not pass through the filtration membrane of the glomerulus into the filtrate. How do the kidneys ensure that these waste products get excreted in urine?
by utilizing secretion -Secretion moves selected substances from the blood into the filtrate for excretion.
The macula densa cells respond to _____
changes in Na+ content of the filtration.
The descending limb of the nephron loop ________
contains fluid that becomes more concentrated as it moves down into the medulla
Glomerular filtration is a process of bulk flow driven by
glomerular hydrostatic pressure.
An increase in the permeability of the cells of the collecting tubule to water is due to a(n) ________.
increase in production of ADH (anti-diurectic hormone)
The functional and structural unit of the kidneys is the ________.
nephron
Reabsorption of high levels of glucose and amino acids in the filtrate is accomplished by ________.
secondary active transport
The renal corpuscle consists of two parts, the glomerular capillaries and __________.
the glomerular capsule
In the ascending limb of nephron loop the ______
thick segment moves ions out into interstitial spaces for reabsorption
Glucose reabsorption utilizes transport proteins in the proximal convoluted tubule cells to move glucose into the blood. The maximum amount of glucose that can be transported when all of the transport proteins are full is known as the ___________. Any remaining glucose will be excreted in the urine.
transport maximum -The transport maximum is determined by the number of transport proteins available to move glucose into the blood.
Lower than normal NaCl concentration in the ascending limb of the nephron loop will cause the afferent arterioles to __________.
vasodilate
