STRUCTURAL AND FUNCTIONAL ORGANIZATION OF THE URINARY SYSTEM Flashcards
1
Q
What does the urinary system consist of?
A
wo kidneys,
two ureters,
one urinary bladder, and
one urethra
2
Q
After the kidneys filter the blood, they return _______ to the bloodstream
A
most of the water and many solutes
3
Q
What is the scientific study of the anatomy, physiology, and disorders of the kidneys
A
Nephrology
4
Q
What is the branch of medicine that deals with the male and female urinary system, and the male reproductive system?
A
Urology
5
Q
Functions of the Kidneys
A
Regulation of ion levels in the blood
Regulation of blood volume and blood pressure
Regulation of blood pH
Production of hormones
Excretion of wastes
6
Q
Regulation of ion levels in the blood
The kidneys help regulate the blood levels of several ions, most importantly…..
A
sodium ions (Na+), potassium ions (K+), calcium ions (Ca2+), chloride ions (Cl-), phosphate ions (HPO4^2-)
7
Q
Regulation of blood volume and blood pressure.
The kidneys adjust the volume of blood in the body by doing what?
A
returning water to the blood
eliminating it in the urine
8
Q
Regulation of blood volume and blood pressure
the Kidneys regulate blood pressure by secreting the enzyme __________, which activates the renin–angiotensin–aldosterone pathway, by adjusting blood flow into and out of the kidneys, and by adjusting blood volume
A
renin
9
Q
Regulation of blood pH
The kidneys regulate the concentration of H+ in the blood by a __________ variable amount of H+ in the urine.
A
excreting
10
Q
Regulation of blood pH.
The kidneys conserve, _________ which is an important buffer of H+.
A
blood bicarbonate ions (HCO3)
11
Q
Production of hormones
The kidneys produce what two hormones, what do they do?
A
1) Calcitriol, the active form of vitamin D, helps regulate calcium homeostasis
2) Erythropoietin, stimulates production of red blood cells.
12
Q
Excretion of wastes.
By forming _____, the kidneys help excrete wastes
A
urine
13
Q
Excretion of wastes.
What are parts of urine?
A
1) Ammonia and urea
2) Bilirubin
3) Creatinine
4) Uric acid
5) Other wastes excreted in urine are foreign substances from the diet, such as drugs and environmental toxins.
14
Q
What part of the urine is from the breakdown of amino acids?
A
Ammonia and urea
15
Q
What part of the urine is from the breakdown of hemoglobin
A
Bilirubin
16
Q
What part of the urine is from the breakdown of creatine phosphate in muscle fibers?
A
Creatinine
17
Q
What part of the urine is from the breakdown of nucleic acids
A
Uric acid
18
Q
What are the pair of reddish organs shaped like kidney beans
A
kidneys……..
19
Q
Where re the kidneys located?
A
abdominal cavity at the level of the 12th thoracic and first three lumbar vertebrae
20
Q
True/false
The LEFT kidney is slightly lower than the RIGHT because the liver occupies a large area above the kidney on the right side.
A
FALSE
the right is lower
21
Q
External Anatomy of the Kidneys
Near the center of the medial border is an indentation called the __________, through which the ureter leaves the kidney and blood vessels, lymphatic vessels, and nerves enter and exit.
A
renal hilum
22
Q
External Anatomy of the Kidneys
Surrounding each kidney is the ___________, a connective tissue sheath that helps maintain the shape of the kidney and serves as a barrier against trauma
A
smooth transparent renal capsule
23
Q
External Anatomy of the Kidneys
What surrounds the renal capsule and cushions the kidney. Along with a thin layer of dense irregular connective tissue, this also anchors the kidney to the posterior abdominal wall.
A
Adipose (fatty) tissue
24
Q
Internal Anatomy of the Kidneys
Internally, the kidneys have two main regions. What are they?
A
Renal cortex
Renal medulla
25
Internal Anatomy of the Kidneys
What region of the kidney?
the outer light-red region
Renal cortex
26
Internal Anatomy of the Kidneys
What region of the kidney?
inner, darker red-brown region
Renal medulla
27
Internal Anatomy of the Kidneys
Within the _________ are several cone-shaped renal pyramids. Extensions of the \_\_\_\_\_\_\_\_, called renal columns, fill the spaces between renal pyramids.
- renal medulla
- renal cortex
28
Internal Anatomy of the Kidneys.
Urine formed in the kidney passes from thousands of papillary ducts within the renal pyramids into cuplike structures called what?
minor calyces
29
Internal Anatomy of the Kidneys
Each kidney has how many minor calyces?
8-12
30
From the Minor Calyces, urine next flows into 2-3 major calyces, and then into a single large cavity called the \_\_\_\_\_\_\_.
renal pelvis
31
Internal Anatomy of the Kidneys
The renal pelvis drains urine into a ______ which transports urine into the urinary bladder for storage and eventual elimination from the body.
ureter
32
Renal Blood Supply
About what percent of the resting cardiac output flows into the kidneys through the right and left renal arteries
20-25%
| (1200 milliliters of blood per minute)
33
Renal Blood Supply.
Within each kidney, the renal artery divides into smaller and smaller vessels (segmental, interlobar, arcuate, interlobular arteries) that eventually deliver blood to the \_\_\_\_\_\_\_\_.
afferent arterioles
34
Renal Blood Supply
Each afferent arteriole divides into a tangled capillary network called a \_\_\_\_\_\_\_\_.
glomerulus
35
Renal Blood Supply
(a) Each afferent arteriole divides into a tangled capillary network called a \_\_\_\_\_\_\_.
(b) The capillaries of the glomerulus reunite to form an efferent arteriole.
(c) Upon leaving the glomerulus, each efferent arteriole divides to form a network of capillaries around the\_\_\_\_\_\_\_\_\_\_
(a) glomerulus
(c) kidney tubules
36
What are the blood vessels called in the kidney?
interlobular, arcuate, and interlobar veins and arteries
37
Renal Blood Supply
Ultimately, all interlobular, arcuate, and interlobar veins drain into what?
renal vein
38
The functional units of the kidney are the \_\_\_\_\_\_, numbering about a million in each kidney.
nephrons
39
A nephron consists of what two parts... what do they do?
(a) Renal corpuscle, where blood plasma is filtered.
(b) Renal tubule into which the filtered fluid, called glomerular filtrate, passes.
40
As the fluid moves through the renal tubules, wastes and excess substances are added, and useful materials are returned to the blood in the \_\_\_\_\_\_\_\_\_.
peritubular capillaries
41
The two parts that make up a renal corpuscle are the
glomerulus
glomerular (Bowman's) capsule
42
what is a double-walled cup of epithelial cells that surrounds the glomerular capillaries
glomerular (Bowman's) capsule,
43
Functions performed by the nephron
To produce urine, nephrons and collecting ducts perform three basic processes which include what???
glomerular filtration, tubular reabsorption, and tubular secretion
44
the basic functions performed by the nephron
\_\_\_\_\_\_\_ is the forcing of fluids and dissolved substances smaller than a certain size through a membrane by pressure
Filtration
45
\_\_\_\_\_\_\_\_ is the first step of urine production. Blood pressure forces water and most solutes in blood plasma across the wall of glomerular capillaries, forming glomerular filtrate.
Glomerular filtration
46
the basic functions performed by the nephron
\_\_\_\_\_\_\_\_ occurs as filtered fluid flows along the renal tubule and through the collecting duct:
Tubular reabsorption
47
Tubule and duct cells return about \_\_% of the filtered water and many useful solutes to the blood flowing through peritubular capillaries.
99%
48
\_\_\_\_\_\_\_\_\_ also takes place as fluid flows along the tubule and through the collecting duct
Tubular secretion
49
The tubule and duct cells remove substances, such as ___________ from the blood peritubular capillaries and transport them into the fluid in the renal tubules.
wastes, drugs, and excess ions
50
The basic functions performed by the nephron.
By the time the filtered fluid has undergone tubular reabsorption and tublar secretion and enters the minor and major calyx it is called what?
Urine
51
As nephrons perform their functions, they help maintain homeostasis of the blood's \_\_\_\_\_\_\_\_\_\_
volume and composition
52
True/False
Urine values vary considerably according to diet
True
53
Glomerular Filtration
The cells that make up the inner wall of the glomerular capsule, called \_\_\_\_\_\_\_\_\_, adhere closely to the endothelial cells of the glomerulus.
podocytes
54
Simple squamous epithelial cells form the _______ layer of the glomerular capsule.
outer
55
Together, the podocytes and glomerular endothelium form a __________ that permits the passage of water and solutes from the blood into the capsular space.
filtration membrane
56
Glomerular Filtration
## Footnote
Blood cells and most plasma proteins remain in the blood due to what?
they are too large to pass through the filtration membrane
57
Net Filtration Pressure
## Footnote
What is the pressure that causes filtration in the glomerular capillaries?
Blood Pressure?
58
Net Filtration Pressure
What two pressures OPPOSE glomerular filtration
Blood colloid osmotic pressure
Glomerular capsule pressure
59
When either of the OPOSING pressures increases what happens to glomerular filtration?
decreases
60
Normally blood pressure is greater than the two opposing pressures producing a net filteration pressure by about what?
10mmHg
61
Net filtration pressure forces a large volume of fluid into the capsular space, about
\_\_\_\_\_\_ liters daily in females and _____ liters daily in males.
150 liters daily in females
180 liters daily in males
62
Net filtration pressure can be summarized as
Net filtration pressure =
glomerular capillary blood pressure -(blood colloidal osmotic pressure + glomerular capsule pressure).
63
How do the efferent and afferent arterioles effect Net Filtration Pressure pressure?
- Efferent arteriole is smaller in diameter than the afferent arteriole, it helps raise the blood pressure in the glomerular capillaries
- blood pressure increases or decreases slightly, changes in the diameters of the afferent and efferent arterioles can actually keep net filtration pressure steady to maintain normal glomerular filtration
-
64
Constriction of the ________ arteriole decreases blood flow into the glomerulus, which decreases net filtration pressure.
afferent
65
Constriction of the _______ arteriole slows outflow of blood and increases net filtration pressure.
efferent
66
The amount of filtrate that forms in both kidneys every minute is called what?
glomerular filtration rate (GFR).
67
In adults, the GFR is about
\_\_\_ mL/min in females and ____ mL/min in males
105 mL/min in females and 125 mL/min in males
68
If the GFR is too \_\_\_\_\_, needed substances pass so quickly through the renal tubules that they are unable to be reabsorbed and pass out of the body as part of urine.
High
69
if the GFR is too \_\_\_\_, nearly all the filtrate is reabsorbed and waste products are not adequately excreted.
Low
70
What is the hormone that promotes loss of sodium ions and water in the urine in part because it increases glomerular filtration rate?
Atrial natriuretic peptide (ANP)
71
Atrial Natriuretic Peptide (ANP)
Cells in the atria of the heart secrete more ANP if the ______ is stretched more, as occurs when blood volume increases.
ANP then acts on the _______ to increase loss of sodium ions and water in urine, which reduces the blood volume back to normal.
- Heart
- kidneys
-
72
Atrial Natriuretic Peptide (ANP)
The blood vessels of the kidneys ae by sympathetic neurons of the autonomic nervous system and when active, cause \_\_\_\_\_\_\_.
(a) At rest, sympathetic stimulation is low and the afferent and efferent arterioles are relatively \_\_\_\_\_\_\_.
(b) With greater sympathetic stimulation, as occurs with exorcise or hemorrhage, the afferent arterioles are _________ more than the efferent arterioles.
(c) As a result, blood flow into the glomerular capillaries is greatly \_\_\_\_\_\_\_, net filtration pressure drops, and GFR drops.
(d) These changes ________ urine output, which helps conserve blood volume and permits greater blood flow to other body tissues.
vasoconstriction
(a) dilated
(b) constricted
(c) decreased
(d) reduce
73
What is defined as returning most of the filtered water and many of the filtered solutes to the blood
-is the second basic function of the nephrons and collecting ducts.
Tubular reabsorption
74
Tubular Reabsorption and Secretion.
## Footnote
The filtered fluid becomes \_\_\_\_\_\_\_\_once it enters the proximal convoluted tubule.
Due to reabsorption and secretion, the composition of tubular fluid changes as it flows along the nephron tubule and through a \_\_\_\_\_\_.
- tubular fluid
- collecting duct
75
Tubular Reabsorption and Secretion.
## Footnote
Typically, about \_\_% of the filtered water is reabsorbed.
(a) Only \_% of the water in glomerular filtrate actually leaves the body in urine, the fluid that drains into the renal pelvis.
- 99%
- 1%
76
Epithelial cells all along the renal tubules and collecting ducts carry out tubular reabsorption.
(a) Some solutes are passively reabsorbed by diffusion; others are reabsorbed by active transport.
(b) Proximal convoluted tubule cells make the largest contribution, reabsorbing WHAT?
- 65% of the filtered water,
- 100% of the filtered glucose and amino acids
- large quantities of various ions such as sodium (Na+), potassium (K+), chloride (Cl-), bicarbonate (HCO3 -), calcium (Ca2+), and magnesium (Mg2+).
77
Tubular Reabsorption and Secretion
## Footnote
Reabsorption of solutes also promotes reabsorption of _____ in the following way.
water
78
The third function of the nephrons and collecting ducts is \_\_\_\_\_\_\_\_\_\_, the transfer of materials from the blood through tubule cells and into tubular fluid.
tubular secretion
79
Tubular Reabsorption and Secretion.
## Footnote
Secreted substances include hydrogen ions (H+), potassium K+, ammonia (NH3), urea, creatinine (a waste from creatine in muscle cells), and certain drugs such as penicillin. Tubular secretion helps _______ these substances from the body.
eliminate
80
Tubule cell secretion of excess K+ for elimination in the urine also is very important why?
to maintain a stable level of K+ in body fluids.
81
Tubular secretion also helps control a blood pH of what?
pH of 7.35 to 7.45
82
To eliminate acids, the cells of the renal tubules secrete what into the tubular fluid?
H+
83
Urine is typically alkaline or ?
acidic
84
The most important hormonal regulators of ion reabsorption and secretion are what?
angiotensin II and aldosterone
85
In the proximal convoluted tubules, angiotensin II enhances reabsorption of what?
Na+ and Cl-
86
Angiotensin II also stimulates the adrenal cortex to release what?
aldosterone
87
what hormone stimulates the tubule cells in the last part of the distal convoluted tubules and throughout the collecting ducts to reabsorb more Na+ and Cl- and secrete more K+.
Aldosterone
88
An elevated level of K+ in plasma causes what?
serious disturbances in cardiac rhythm or even cardiac arrest.
89
The major hormone that regulates water reabsorption is what? How does it operate?
antidiuretic hormone (ADH)
operates via negative feedback.
90
When the concentration of water in the blood decreases by as little as \_\_\_%, osmoreceptors in the hypothalamus stimulate release of ADH from the posterior pituitary.
1%
91
A second powerful stimulus for _______ secretion is a decrease in blood volume, as occurs in hemorrhaging or severe dehydration.
ADH
92
Lower-than-normal level of Ca2+ in the blood stimulates the parathyroid glands to release what? what does it do?
parathyroid hormone (PTH)……
## Footnote
PTH stimulates cells in the early distal convoluted tubules to reabsorb more Ca2+ into the blood.
93
The kidneys can produce as little as ______ mL of very concentrated urine each day when ADH concentration is maximal, for instance during severe dehydration
400–500
94
What hormone also inhibits HPO4^2- (phosphate) reabsorption in proximal convoluted tubules, promoting phosphate excretion.
PTH
95
An analysis of the volume and physical, chemical, and microscopic properties of urine called a \_\_\_\_\_\_\_, tells much about the state of the human body.
urinalysis
96
Components of Urine
## Footnote
The volume of urine eliminated per day in a normal adult is \_\_\_\_\_\_\_. Water accounts for about\_\_\_\_\_% of the total volume of urine.
1 to 2 liters (about 1 to 2 quarts)
95%
97
What transports urine from the renal pelvis of one of the kidneys to the urinary bladder.
Each of the two ureters
98
What prevents backflow of urine when pressure builds up in the
bladder during urination.
ureters pass under the urinary bladder for several centimeters, causing the bladder to compress the ureters
99
The wall of the ureter consists of what three layers?
The inner layer is the mucosa
The middle layer consists of smooth muscle
The outer layer consists of areolar connective
100
What layer of the wall of the ureter?
## Footnote
containing transitional epithelium with an underlying layer of areolar connective tissue
mucosa
101
What layer of the wall of the ureter?
use peristaltic contractions to move urine towards the bladder
middle layer of smooth muscle
102
What layer of the wall of the ureter?
## Footnote
areolar connective tissue containing blood vessels,
lymphatic vessels, and nerves
The outer layer
103
Urinary bladder capacity averages about what?
700–800 mL
104
What covers the superior surface of the bladder?
What covers the rest?
peritoneum
Fibrous outer covering
105
The muscular layer of the urinary bladder wall consists of three layers of smooth muscle called the what?
detrusor muscle
106
What are the two ureteral sphincters? which one is voluntarily
Internal sphincter - involuntary
External sphincter - voluntary
107
The urinary bladder stores urine prior to its elimination and then expels urine into the urethra by an act called \_\_\_\_\_, commonly known as urination.
micturition
108
When the volume of urine in the urinary bladder exceeds _____ mL, pressure within the bladder increases considerably, and stretch receptors in its wall transmit nerve impulses into the spinal cord.
-These impulses propagate to the lower part of the spinal cord and trigger a reflex called the \_\_\_\_\_\_\_\_\_.
200 to 400
micturition reflex
109
lean adults, body fluids make up between \_\_\_\_% of total body mass.
55% and 60%
110
These each define what?
1. About two-thirds of body fluid is or cytosol, the fluid within cells.
2. The other third, called, is outside cells and includes all other body fluids.
1. intracellular fluid (ICF)
2. extracellular fluid (ECF)
111
About \_\_\_% of the ECF is interstitial fluid, which occupies the spaces between tissue cells, and about \_\_% of the ECF is blood plasma, the liquid portion of the blood.
80% interstitial
20% blood plasma
112
extracellular fluids that are grouped with interstitial fluid include:
1) lymph in lymphatic vessels;
2) cerebrospinal fluid in the nervous system;
3) synovial fluid in joints;
4) aqueous humor and vitreous body in the eyes;
5) endolymph and perilymph in the ears;
6) pleural, pericardial, and peritoneal fluids between serous membranes of the lungs,
heart, and abdominal organs.
113
Two “barriers” separate intracellular fluid, interstitial fluid, and blood plasma:
plasma membrane
Blood vessel walls
114
Only where in the body are the walls thin enough and leaky
enough to permit the exchange of water and solutes between blood plasma and interstitial fluid?
Only in capillaries
115
Water is by far the largest single component of the body, making up \_\_\_\_\_\_% of total body mass, depending on age and gender.
45–75%
116
Why does concentration of solutes in ECF and interstitial fluids determines the direction of water movement ?
Because osmosis is the primary means of water movement
117
The main sources of body water are
- ingested liquids (about 1600 mL) and
- moist foods (about 700 mL) absorbed from the gastrointestinal (GI) tract,
- which total about 2300 mL/day.
118
True/False
the body can also cant water during chemical reactions
True
Most of it is produced during aerobic cellular respiration
119
Metabolic water gain accounts for about ____ mL/day
200 mL/day
120
daily water gain totals about \_\_\_\_\_mL
2500 mL
121
When body mass decreases by 2% due to fluid loss, _____ exists. A decrease in blood volume causes blood pressure to fall.
mild dehydration
122
What is known as the thirst center governs the urge to drink
An area in the hypothalamus
123
The extent of ______ is the main factor that determines body fluid volume
urinary salt (NaCl) loss
124
True/False
The electrolyte content of intracellular fluid differs little from that of extracellular fluid.
FALSE
differs considerably
125
\_\_\_\_\_\_\_ are the most abundant extracellular ions, representing about 90% of extracellular cations.
- plays a pivotal role in fluid and electrolyte balance because it accounts for almost half of the osmotic pressure of extracellular fluid.
- is necessary for the generation and conduction of action potentials in neurons and muscle fibers.
Na+
126
\_\_\_\_are the most prevalent anions in extracellular fluid. Because most plasma membranes contain many Cl- leakage channels, Cl- moves easily between the extracellular and intracellular compartments.
Chloride ions (Cl-)
127
What is the most abundant cations in intracellular fluid, play a key role in establishing the resting membrane potential and in the repolarization phase of action potentials in neurons and muscle fibers?
-When this moves into or out of cells, it often is exchanged for H+ and thereby helps regulate the pH of body fluids.
Potassium ions (K+)
128
The level of K+ in blood plasma is controlled mainly by
aldosterone
129
1) When blood plasma K+ is\_\_\_ , more aldosterone is secreted into the blood. how does this work?
high
Aldosterone then stimulates the renal collecting ducts to secrete more K+ and excess K+ is lost in the urine.
130
About **% of the calcium in adults is in the skeleton and teeth, where it is combined with phosphates to form \_\_\_\_\_\_.**
98
Mineral salts
131
1. In body fluids, calcium is mainly \_\_\_\_\_\_\_
2. The two main regulators of Ca2+ level in blood plasma are ______ and \_\_\_\_\_\_\_
1. extracellular cation
2. parathyroid hormone (PTH) and calcitriol (vitamin D that acts as a hormone)
132
True/False
A major homeostatic challenge is keeping the H+ level (pH) of body fluids in the appropriate range.
True
133
the maintenance of acid–base balance—is of critical importance why?
because the three-dimensional shape of all body proteins that allows them to function, are very sensitive to the most minor changes in pH
134
When the diet contains a large amount of protein, as is typical in North America, effects pH how?
cellular metabolism produces more acids than bases and thus tends to acidify the blood.
135
What are the principal buffer systems of the body fluids?
Protein Buffer System
Carbonic Acid–Bicarbonate Buffer System
Phosphate Buffer System
136
What is the most abundant buffer in intracellular fluid and plasma?
Protein Buffer System
137
What can buffer both acids and bases?
Protein buffer system
138
What buffer system is based on the bicarbonate ion (HCO3 -), which can act as a weak base, and carbonic acid (H2CO3), which can act as a weak acid.
carbonic acid–bicarbonate buffer system
139
Are carbonic acid–bicarbonate buffer excreted in urine? Why?
No
Because the kidneys reabsorb filtered HCO3 -,
140
What buffer system acts via a mechanism similar to the carbonic acid– bicarbonate buffer system?
The phosphate buffer system
141
Because the concentration of phosphates is highest in \_\_\_\_\_\_\_, the phosphate buffer system is an important regulator of pH in the \_\_\_\_\_\_. It also acts to a smaller degree in extracellular fluids, and it buffers acids in urine.
intracellular fluid
cytosol
142
Breathing Slowly releases less CO2 effecting blood pH how?
Blood PH falls
143
\_\_\_\_\_\_\_ is a condition in which arterial blood pH is below 7.35.
Acidosis
144
What is it called when arterial blood pH is higher than 7.45
alkalosis
145
A major physiological effect of _______ is over-excitability in both the central nervous system and peripheral nerves.
## Footnote
-Neurons conduct impulses repetitively, even when not stimulated; the results are nervousness, muscle spasms, and even convulsions and death.
alkalosis
146
The principal physiological effect of acidosis is
depression of the central nervous system through depression of synaptic transmission.
147
If the systemic arterial blood pH falls below \_\_\_\_\_, depression of the nervous system is so severe that the individual becomes disoriented, comatose, and may die.
7
148
If a person has altered blood pH due to metabolic causes what can help bring blood pH back to normal range? how long does it take?
hyperventilation or
hypoventilation
occurs within minutes and reaches its maximum within hours
149
If a person has altered blood pH due to respiratory causes what can help correct this how long does it take?
Renal compensation—changes in secretion of H+ and reabsorption of HCO3 - by the kidney tubules—can help reverse the change.
may begin in minutes, but it takes days to reach maximum effectiveness
150
kidneys excrete about\_\_\_\_\_ mL in urine
\_\_\_\_ mL evaporates from the skin
Lungs exhale about ___ mL
gastrointestinal tract \_\_\_\_\_mL
Kidneys 1500
skin 600
Lungs 300
Gastrointestinal 100
151
lean adults, body fluids make up between \_\_\_\_% of total body mass.
55% and 60%
152
The wall of the ureter consists of what three layers?
The inner layer is the mucosa
The middle layer consists of smooth muscle
The outer layer consists of areolar connective
