Lecture: The Urinary System Flashcards
1
Q
What is the ph of urine?
A
4.5-8 (avg 6)
2
Q
What is the water content of urine?
A
93-97%
3
Q
How much urine does a human pass a day?
A
700-2000 mL per day
4
Q
What external factors contributes to the amount of urine passed?
A
temperature, humidity, and water intake
5
Q
What is polyuria?
A
A higher than normal volume of urine
6
Q
What is Anuria
A
No urine
7
Q
What is oliguria?
A
A lower than normal volume of urine
8
Q
What is one of the most important symptoms of diabetes
A
polyuria
9
Q
What is Hematuria?
A
Red peep urine
10
Q
What is pyuria?
A
Smoky colored urine
11
Q
What is jaundice?
A
Deeply yellow urine
12
Q
What is Diabetes Insipidus?
A
Excessive urination and extreme thirst as a result of inadequate output of ADH
13
Q
Where does bilirubin come from?
A
Destruction of RBC’s
14
Q
What gives urine its yellow color?
A
Bilirubin
15
Q
What is the bacterial content of urine?
A
None (sterile)
16
Q
What is the compound created by deamination of amino acids by liver and kidneys?
A
Urea
17
Q
If someone has a muscular disease and it atrophies, what may increase in the urine?
A
Creatinine
18
Q
What parts make up the urinary tract?
A
Ureters, Urinary Bladder, Urethra
19
Q
What is a fancy word for Urination?
A
Micturition
20
Q
Where is the bladder positioned in a female that is different from the male?
A
female: the uterus sits on top of the bladder
21
Q
How much does the uterus weigh in a non vs pregnant woman
A
50 grams vs 200grams
22
Q
At what volume does one feel the urge to urinate?
A
150 mL
23
Q
At what volume does the bladder feel full?
A
500 mL
24
Q
How frequently does peristalsis move urine along the tract?
A
Every 30 seconds
25
How is remaining urine emptied after urination in men?
The bulbo spongeousus/cavernous contracts
26
How is remaining urine emptied after urination in women?
It is emptied by gravity
27
What muscle allows voluntary control over urination?
External urethral sphincters
28
Which nervous systems control urination?
The parasympathetic AND sympathetic nervous systems
29
What is the byproduct of protein metabolism?
Ammonium Ion (NH4)
30
Through which compound is ammonia disposed of?
Urea (urine cycle)
31
In what organ does urea cycling take place?
The liver
32
Which is more toxic? Urea or Ammonium
Ammonium
33
What are the 3 major byproducts of protein synthesis into energy?
Urea, Uric acid, creatinine
34
What are the 2 garbage collecting organs?
Liver + Kidneys
35
How many kidneys are there?
2
36
In which abdominal cavity are kidneys located?
Right + Left lumbar region
37
Which kidney is lower?
The right kidney
38
Which kidney is protected by the 12th rib?
Right kidney
39
Which kidney is protected by the 11 + 12th rib?
Left kidney
40
How long is the typical adult kidney?
10cm
41
How long are the ureters?
10-12 inches
42
Which wall is the kidney closer to?
Posterior wall, retroperitoneal
43
What are the 3 functions of the urinary system?
1. Excretion 2. Elimination 3.Homeostatic regulation
44
Which organ produces urine?
The kidneys
45
What are the 3 parts of the urinary tract?
1. Ureters 2. Urinary bladder 3. Urethra
46
Which organ (or group of organs) eliminates urine?
The urinary tract
47
How does urination occur?
The muscular urinary bladder contacts, forcing urine through urethra and out of body
48
What are five homeostatic functions of the urinary system?
1. Regulates blood volume/pressure
2. Regulates plasma ion concentration
3. Stabilizes blood pH
4. Conserves nutrients
5. Assists liver in detoxification
49
How is blood volume and pressure regulated by the urinary system? (2)
1. Adjusting volume of water lost in urine
| 2. Releasing erythropoietin and renin
50
How is plasma ion concentration regulated by the urinary system?
1. Controlling quantities of sodium potassium and chloride ions lost in urine
2. Synthesizes of calcitrol to regulate calcium ion levels
51
How is blood pH stabilized by the urinary system? (ions)
By controlling loss of hydrogen ions and bicarbonate ions in urine
52
How are nutrients conserved by the urinary system?
By preventing excretion while excreting waste
53
What is superior to both kidneys?
Suprarenal (adrenal) glands
54
What 3 things protect and stabilize the kidneys?
1. Fibrous capsule 2. Perinepheric fat capsule 2. Renal fascia
55
What is the perinepheric fat capsule composed of?
A thick layer of adipose tissue (fat)
56
What is the fibrous capsule composed of?
A layer of collagen fibers
57
What is the renal fascia composed of?
A dense fibrous outer layer
58
What exits at the kidney hilum?
The renal vein and ureter
59
What stabilizes positions of ureter, renal blood vessels, and nerves?
The renal sinus
60
What is the renal cortex?
Superficial portion of kidney in contact with renal capsule
61
How does the renal cortex appear?
Reddish brown and granular
62
What are renal pyramids?
6-18 distinct conical or triangular structures in renal medulla
63
What is a renal papilla?
The tip of a renal pyramids that projects into the renal sinus
64
What are renal columns?
Bands of cortical tissue separate adjacent renal pyramids
65
How is the texture of a renal column?
Distinctly granular
66
What parts does a renal lobe consist of? What does it do?
1. Renal pyramid 2. renal cortex 3. renal columns 4. Produce Urine
67
How does urine first leave the kidneys?
Ducts discharge urine from the renal papilla to the minor calyx
68
What do minor calyxes form?
4-5 minor calyx forms 1 major calyx
69
What is the renal pelvis?
A Large, funnel-shaped chamber comprised of 2-3 major calyces.
70
What is the position of the renal pelvis?
Fills most of renal sinus and connected to the ureter
71
Where does urine production begin?
In the nephrons
72
What is a nephron?
A Microscopic, tubular structures in cortex of each renal lobe
73
How much of the total cardiac output (of blood) do the kidneys receive?
20-25%
74
How much blood flows through the kidneys per minute?
1200 mL
75
Through what do the kidneys receive blood?
The renal artery
76
What enters the kidney at the hilum?
Renal nerves
77
What innervates the kidneys and ureters?
Renal nerves
78
What stimulates release of renin by the kidneys?
1. sympathetic nervous system activity
2. A decrease in sodium chloride (salt) in the kidney
3. a fall in arterial blood pressure
79
What nervous system adjusts rate of urine formation?
Sympathetic Innervation, by changing blood flow and pressure at nephron
80
A nephron consists of what 2 parts?
A renal tubule and renal corpuscle
81
Where is the glomerulus?
Inside the renal corpuscle
82
What is the glomerulus?
A network of 50 intertwining capillaries
83
How does blood enter and exit the glomerulus?
Through afferent (arrive) and efferent (exit) arterioles
84
In which part of the kidney does filtration occur?
The renal corpuscle
85
How does blood pressure aid in filtration? What does it produce?
1. Forces water and solutes out of glomerular capillaries into capsular space
2. Produces protein-free solution (filtrate) similar to plasma
86
The renal tubules reabsorb… how much water?
useful organic nutrients that enter filtrate and more than 90% of water in filtrate
87
The renal tubules secrete…
Secrete waste products that failed to enter the corpuscle via filtration
88
What is the collecting system?
A series of tubes that carries tubular fluid away from the nephrons
89
Describe the organization of a nephron
Traveling along tubule, filtrate (tubular fluid) gradually changes composition
90
From where do collecting ducts receive filtrate? (NOT A PART OF THE NEPHRON)
Each duct receives filtrate from many nephrons
91
Each collecting duct begins ______, descends into ________. Then it carries filtrate to _________ and finally drains into _________.
1. The cortex 2. The medulla 3. Papillary ducts 4. A minor Calyx
92
What type of cells make up a collecting duct?
Cuboidal to columnar cells
93
What type of cells make up a papillary duct?
Columnar cells
94
What type of cells make up a nephron loop?
Squamos or low cuboidal cells
95
What type of cells make up a renal tubule?
Cuboidal cells with microvilli (except for the DCT)
96
What type of nephron makes up 85% of nephrons?
Cortical nephrons
97
Where are cortical nephrons located?
Inside the superficial cortex of the kidney
98
What type of nephron has a short nephron loop?
Cortical nephrons
99
What type of nephron makes up 15% of nephrons?
Juxtamedullary nephrons
100
Describe the nephron loop of the Juxtamedullary nephrons?
The nephron loops extend deep into medulla
101
What is the diameter of a renal corpuscle?
150–250 µm
102
What special cells make up the visceral epithelium of the kidneys?
They are large cells called podocytes with complex “feet” (pedicels)
103
Which capillaries of the kidneys are fenestrated?
Glomerular capillaries
104
Which cells regulate blood flow of kidney capillaries?
Mesengial cells
105
The filtration membrane of the renal corpuscle consists of what 3 layers?
1. Fenestrated epithelium
2. Lamina densa
3. Filtration cells
106
What is the lamina densa?
The central layer of the renal corpuscle
107
Passive filtration at the renal corpuscle allows _________ solutes into _________?
1. metabolic waste, excess ions, glucose, fatty acids, amino acids, and vitamins 2. The capsular space
108
Where does reabsorption mainly occur?
The proximal convoluted tubule
109
What is the first segment of the renal tubule?
The proximal convoluted tubule
110
Describe the epithelial lining of the proximal convoluted tubule?
1. simple cuboidal with microvilli
| 2. Functions in reabsorption, secretion
111
Tubular cells absorb _______ from _______and release them _______?
1. Organic nutrients, ions, water, plasma proteins 2. Tubular fluid 3. Into peritubular fluid
112
What is the third segment of the renal tubule?
The distal convoluted tubule
113
What are the 3 main internal regions of the kidney?
The renal cortex, renal medulla, and renal pelvis
114
What are the 3 functional divisions of the loop of henle?
1. the thin descending limb
2. thin ascending limb
3. thick ascending limb
115
What is the second segment of the renal tubule?
The loop of henle
116
Which segment of the renal tubule has a smaller diameter and epithelial cells that lack microvilli?
The distal convoluted tubule
117
What are the 3 processes at the distal convoluted tubule?
1. Secretion of ions, acids, drugs, and toxins
2. Reabsorption of sodium and calcium ions from tubular fluid
3. Reabsorption of water which concentrates tubular fluid
118
What is the Juxtaglomerular complex?
An endocrine structure that secretes erythropoietin (hormone) and renin (enzyme)
119
The Macula densa Juxtaglomerular cells combine to form what?
the Juxtaglomerular complex
120
What cells compose the macula densa?
Tall epithelial cells with densely clustered nuclei
121
Where is the macula densa?
In the distal convoluted tubule, near the renal corpuscle
122
What do juxtaglomerular cells form?
Smooth muscle fibers in wall of afferent arteriole
123
What adjusts fluid composition while transporting tubular fluid from nephron to renal pelvis?
Collecting ducts
124
Where is final osmotic concentration and volume of urine determined?
Collecting ducts
125
What is the number one goal of urine production?
To maintain homeostasis
126
How does urine production maintain homeostasis?
By regulating volume and composition of blood including excretion of metabolic waste products
127
What are the 3 organic waste products in urine?
1. Urea 2. Creatinine 3. Uric acid
128
Removal of organic waste products from the body is accompanied by ___________?
Water loss
129
What are the 2 major functions of the kidneys?
1. To concentrate filtrate by glomerular filtration
| 2. Absorb and retain valuable materials for use by other tissues
130
What are the 3 basic processes of urine formation
1. Filtration 2. Reabsorption 3. Secretion
131
What forces water through membrane pores of the kidneys?
Hydrostatic pressure
132
Which organ as large pores for filtration?
The liver
133
Reabsorption and secretion involves what 4 processes at the kidneys? (cellular level)
1. Diffusion
2. Osmosis
3. Channel mediated diffusion
4. Carrier mediated transport
134
What are 4 types of carrier mediated transport?
1. Faciliated diffision
2. Active transport
3. Contransport
4. Countertransport
135
What determines the renal threshold?
material remaining in tubular fluid (appearing in urine) that exceeded the capacity of nephron re-absorption.
136
What is the renal threshold?
The plasma concentration at which a compound or ion begins to appear in urine
137
What is the renal threshold of glucose?
approximately 180 mg/dL
138
What is glycosuria?
Glucose in urine
139
What is the renal threshold of amino acids?
65 mg/dL (lower than glucose)
140
What is the term for amino acids appearing in urine?
Aminoaciduria
141
What is the osmotic concentration of body fluids?
300 mOsm/L (milliosmole per liter)
142
Describe glomerular capillaries (4 points)
1. fenestrated capillaries 2. pores 60–100 nm diameter 3. Prevent passage of blood cells 4. Allow diffusion of solutes, including plasma proteins
143
What can diffuse through the lamina densa?
1. Small plasma proteins 2. Nutrients 3. Ions
144
Describe the filtration slits of the glomerulus (3 points)
1. the finest filters 2. gaps only 6–9 nm wide 3. Prevent passage of most small plasma proteins
145
Glomerular filtration is governed by the balance between what 2 things?
1. Hydrostatic pressure (fluid pressure) 2. Colloid osmotic pressure (of materials in solution)
146
What opposes glomerular hydrostatic pressure?
Capsular Hydrostatic Pressure (CsHP)
147
What is the average capusular hydrostatic pressure?
about 15 mm Hg
148
What is Net Hydrostatic Pressure (NHP)?
the difference between Glomerular hydrostatic pressure and capsular hydrostatic pressure
149
What is the colloid osmotic pressure of a solution?
the osmotic pressure resulting from the presence of suspended proteins
150
What are the 2 functions of blood colloid osmotic pressure (BCOP)?
1. To oppose filtration 2. To draw water out of filtrate and into plasma
151
What is the average blood colloid osmotic pressure (BCOP)?
25mm Hg
152
What is filtration pressure (FP)?
The average pressure forcing water and dissolved materials out of glomerular capillaries Into capsular spaces
153
How is filtration pressure calculated at the glomerulus?
It is the difference between Hydrostatic pressure and blood colloid osmotic pressure across glomerular capillaries
154
What is glomerular filtration rate (GFR) ?
the amount of filtrate kidneys produce each minute
155
How much filtrate do the kidneys produce each minute?
Averages 125 mL/min (this is average GFR)
156
What percentage of filtrate is delivered back to the kidneys?
10%
157
What is a creatinine clearance test?
An estimate of glomerular filtration rate (GFR)….. (A more accurate GFR test uses insulin)
158
How much filtrate do glomeruli produce each day?
180 liters
159
What 3 things control GFR?
1. Autoregulation (local level) 2. Hormonal regulation (initiated by kidneys) 3. Autonomic regulation (by sympathetic division of ANS)
160
How is GFR auto-regulated locally?
By changing diameters of afferent arterioles, efferent arterioles, and glomerular capillaries
161
How much of the filtrate produced in the renal corpuscle do PCT cells normally reabsorb?
60–70% of filtrate
162
What are the 5 functions of the proximal convoluted tubule (PCT)?
1. Reabsorption of organic nutrients
2. Reabsorption of water
3. Passive reabsorption of ions
4. Active reabsorption of ions
5. Secretion
163
Three ways sodium ions enter tubular cells in the proximal convoluted tubule (PCT)?
1. Diffusion through leak channels,
2. Sodium-linked cotransport of solutes
3. Countertransport of hydrogen ions
164
What is reabsorbed during countercurrent exchange?
The Nephron loop reabsorbs 1/2 the water and 2/3 of sodium/chloride ions remaining in tubular fluid
165
What is countercurrent multiplication?
The exchange between the thin/descending and the thick/ascending parallel limbs of the loop of henle
166
During countercurrent multiplication, Fluid in descending limb flows _______ while the fluid in ascending limb flows _______.
1. toward renal pelvis 2. toward cortex
167
What separates the parallel segments of the nephron loop?
Only peritubular fluid
168
Which limb of the nephron loop is permeable to water and impermeable to solutes?
The thin descending limb
169
Which limb of the nephron loop is impermeable to water/solutes but contains active transport mechanisms (Na+ and Cl- pumps)?
The thick ascending limb
170
What 2 things happen to tubular fluid as it flows along the thin descending limb?
1. Osmosis moves water into peritubular fluid, leaving solutes behind
2. Osmotic concentration of tubular fluid increases
171
What 2 things happen to tubular fluid as it flows along the thick ascending limb?
1. 2/3 of Na+ and Cl- are pumped out of tubular fluid before it reaches DCT 2. solute concentration in tubular fluid declines
172
What percent of the initial filtrate volume reaches DCT?
15-20%
173
The tubular cells at the DCT transport ________ out of tubular fluid in exchange for ________
1. Na+ and Cl- 2. K+
174
What hormone controls ion pump/channels by stimulating synthesis and incorporation of Na+ pumps/channels?
Aldosterone
175
Where is Aldosterone produced?
The suprarenal cortex
176
What hormone reduces Na+ lost in urine?
Aldosterone
177
What is hypokalemia?
A condition produced by prolonged aldosterone stimulation that dangerously reduces plasma concentration
178
Describe the effects hydrogen ion secretion (3 points)
1. Acidifies tubular fluid
2. Elevates blood pH
3. Accelerates when blood pH falls
179
What are the 2 types of acidosis?
1. Lactic acidosis 2. Ketoacidosis
180
What is caused by exhaustive muscle activity?
Lactic acidosis
181
What is caused by starvation or diabetes mellitus?
Ketoacidosis
182
What causes ketoacidosis?
Starvation or diabetes mellitus
183
How do the kidneys control blood pH?
Through H+ removal and bicarbonate production
184
What is the term for abnormally high blood pH?
Alkalosis
185
What can cause alkalosis?
prolonged aldosterone stimulation
186
What is acidosis?
Increased acidity in the blood (usually plasma) and other body tissues
187
How does the body fight acidosis? (3 steps)
1. PCT and DCT deaminate amino acids
2. Ammonium ions are pumped into tubular fluid
3. Bicarbonate ions enter bloodstream through peritubular fluid
188
What are 2 benefits of tubular deamination?
1. Carbon chains are made for catabolism
| 2. Generates bicarbonate ions to buffer plasma
189
Collecting ducts receive ___1___ from ___2___ and carry it toward ___3___
1. tubular fluid 2. nephrons 3. renal sinus
190
What 3 things are reabsorbed via the collecting system?
1. Sodium ions 2. Bicarbonate 2. Urea
191
__1__ and __2__ are secreted by the collecting system, controlling __3__.
1. Hydrogen ions 2. Bicarbonate ions 3. Body fluid pH
192
How does the body respond to a low pH in peritubular fluid?
Carrier proteins will pump H+ into tubular fluid and reabsorb bicarbonate ions
193
How does the body respond to a high pH in peritubular fluid?
The collecting system will secrete bicarbonate ions and pumps H+ into peritubular fluid
194
What are the vasa recta?
A portion of the peritubular capillary that runs parallel to the loop of henle
195
What are peritubular capillaries?
tiny blood vessels that travel alongside nephrons allowing reabsorption/secretion between blood/the nephron.
196
What is another name for the straight arterioles of the kidneys?
The vasa recta
197
In which 2 places is water reabsorbed by osmosis, contributing to urine volume?
1. Proximal convoluted tubule 2. Descending limb of nephron loop
198
What signal prompts water reabsorption into urine occur?
osmotic concentration of peritubular fluid exceeding that of tubular fluid
199
What is obligatory water reabsorption?
Water movement that cannot be prevented, recovering 85% of filtrate produced
200
Facultative Water Reabsorption accounts for what percent of filtrate volume?
15% or 27L
201
What controls volume of water reabsorbed along DCT and collecting system?
Facultative Water Reabsorption
202
What is Antidiuretic hormone (ADH)?
A hormone helps your kidneys manage the amount of water in your body by causing special water channels to appear in apical cell membranes.
203
A high level of ADH will increase what 3 things?
1. Number of water channels
2. Permeability of DCT and collecting system
3. Rate of osmotic water movement
204
What 2 things will happen if the body lacks ADH?
1. Water will not be reabsorbed
| 2. All fluid reaching DCT is lost in urine, diluting it
205
Where is ADH produced?
Continuously secreted by the posterior pituitary gland
206
How much water will the collecting system reabsorb if ADH levels are normal each day?
9.3% of filtrate or 16.8 L a day.
207
What is diruresis?
increased or excessive production of urine.
208
What are diuretics?
Drugs that promote water loss in urine
209
What is the effect of diuretic therapy?
Reduced:
1. blood volume
2. blood pressure
3. extracellular fluid volume
210
What is the function of the vasa recta?
1. Balance solute reabsorption and osmosis in medulla
| 2. Carries water and solutes out of medulla
211
What 4 categories of compounds are found in urine?
1. Nitrogenous waste
2. Nutrients and metabolites
3. Ions
4. Blood cells
212
What are the 7 nitrogenous wastes found in urine?
1. Urea
2. Creatinine
3. Ammonia
4. Uric acid
5. Hippuric Acid
6. Uronbilin
7. Bilirubin
213
What are the 4 nutrients and metabolites found in urine?
1. Carbohydrates
2. Ketone bodies
3. Lipids
4. Amino Acids
214
What are the 5 ions found in urine?
1. Sodium
2. Chloride
3. Potassium
4. Calcium
5. Magnesium
215
List the 8 steps/stops of renal function.
Step 1: Glomerulus (filtrate production Step 2: Proximal Convoluted Tubule (PCT) (removal of ions and organic substrates) Step 3: PCT and Descending Limb
(concentration of tubular fluid) Step 4: Thick Ascending Limb
(Na+ and Cl- transported out of tubule)
Step 5: DCT and Collecting Ducts
(Final adjustments in composition of tubular fluid) Step 6: DCT and Collecting Ducts
(Final adjustments in volume / osmotic concentration of tubular fluid, Exposure to ADH) Step 7: Vasa Recta
(absorbs solutes /water reabsorbed by nephron) Step 8: Urin production (ends when fluid enters the renal pelvis)
216
What are the structures of urine transport, storage, and elimination?
1. Minor and major calyces
2. renal pelvis
3. ureters
4. urinary bladder
5. proximal portion of urethra
217
What type of epithelium lines the structures of urine transport, storage, and elimination?
transitional epithelium
218
What structures undergo cycles of distention and contraction?
structures of urine transport, storage, and elimination
219
Name the pair of muscular tubes extending from kidneys to urinary bladder and beginning at renal pelvis
The ureters
220
What shape are the ureteral openings? Why?
Slitlike to prevent the backflow of urine when urinary bladder contracts
221
What are the 3 layers of the ureters?
1. Inner mucosa
2. Middle muscular layer
3. Outer connective tissue layer
222
What 2 parts make up the inner mucosa of the ureters?
1. Transitional epithelium
| 2. lamina propria
223
The middle muscular layers of the ureters are comprised of __1__ and __2__ of __3___ muscle.
1. Longitudinal
2. Circular bands of
3. Smooth
224
What is the outer connective tissue layer of the ureters continuous with?
The fibrous renal capsule and peritoneum
225
What phenomena forces urine toward urinary bladder and how often?
Persitaltic contractions every 30 seconds
226
Where do peristaltic contractions begin and where do they proceed?
At the renal pelvis and along the ureters
227
How much urine does a full bladder contain?
1 Liter
228
Which organ of the urinary system is hollow, muscular and functions as temporary reservoir for urine storage?
The urinary bladder
229
What anchors the urinary bladder to pelvic and pubic bones?
Ligamentous bands
230
What is the function of ligamentous bands?
Anchoring the urinary bladder to pelvic and pubic bones
231
Folds in the lining of the urinary bladder that disappear as bladder fills
Rugae
232
What is the trigone of the urinary bladder?
A triangular area of the bladder that acts as a funnel
| that channels urine from bladder into urethra
233
What is the most inferior part of the urinary bladder?
The apex of trigone
234
Where is the urethral entrance?
The apex of trigone
235
What is the region surrounding urethral opening?
The neck of the urinary bladder
236
What is the muscle at the inside the neck of the urinary bladder?
The internal urethral sphincter
237
What kind of muscle makes up the internal urethral sphincter?
Smooth involuntary muscle
238
What innervates the urinary bladder?
1. Postganglionic fibers
| 2. Parasympathetic fibers
239
What are the 3 layers of the urinary bladder?
1. mucosa
2. submucosa
3. muscularis
240
What is the muscular layer of the urinary bladder comprised of?
The detrusor muscle
241
What layers comprise the detrusor muscle?
Inner and outer layers of longitudinal smooth muscle with a circular layer in between
242
What is the function of the detrusor muscle?
compresses urinary bladder and expels urine
243
What extends from neck of urinary bladder To the exterior of the body?
The urethra
244
Approx how long is the male urethra?
18–20 cm; 7-8 in
245
What 3 segments make up the male urethra?
1. Prostatic urethra
2. Membranous urethra
3. Spongy urethra (penile urethra)
246
What part of the urethra extends from urogenital diaphragm to external urethral orifice in a MAN?
Spongy urethra (penile urethra)
247
How does the Prostatic urethra get its name?
It passes through center of prostate gland
248
What part of the urethra includes short segment that penetrates the urogenital diaphragm?
Membranous urethra
249
How long is the female urethra?
3–5 cm; 1-2 in.
250
The external urethral sphincter is comprised of what type of muscle?
Skeletal voluntary muscle
251
How does the external urethral sphincter permit micturution?
Through voluntary RELAXATION
252
What 3 layers make up the urethra?
1. Lamina propria 2. Mucous membrane 3. Mucin-secreting cells
253
What layer of the urethra is thick and elastic?
Lamina propria
254
What layer of the urethra has longitudinal folds?
Mucous membrane
255
What layer of the urethra lies in epethelial pockets?
Mucin-secreting cells
256
The urethra of which sex contains a lamina propria with an extensive network of veins
Female
257
The urethra of which sex contains epithelial mucous glands?
Male
258
The urethra of which sex contains a complex surrounded by concentric layers of smooth muscle
Female
259
The urethra of which sex contains connective tissues in the lamina propria?
Male
260
Which nerves are involved in the Micturition Reflex as the bladder fills with urine?
The afferent and efferent pelvic nerves
261
What prompts the micturition reflex?
Stretch receptors are triggered at a volume of 500ml or more
262
What causes a lack of voluntary control over urination?
1. Infancy
| 2. Incontinence
263
Aging causes a decline in what?
1. The number of functional nephrons
2. GFR
3. sensitivity to ADH
264
What causes incontinence in old age?
Loss of tone in the sphincter muscles
265
What is an effect of an enlarged prostate gland?
Compression of the the urethra and restricts urine flow
266
What systems make up the “excretory system”?
1. Urinary system
2. Integumentary system
3. Respiratory system
4. Digestive system
267
What is the functional unit of the kidney and how many are there?
The nephron, nearly 1 million
268
What are the 2 parts of a nephron?
1. Renal Corpuscle
| 2. Renal Tubule
269
What are the 2 segments of a renal corpuscle?
1. Bowman's Capsule
| 2. Glomerular Capillaries
270
What are the segments of a renal tubule?
1. Proximal convoluted tubule (PCT)
2. Loop of Henle
3. Distal convoluted tubule (DCT)
271
3 major processes by which urine is produced?
1. FIltration
2. Reabsorption
3. Secretion
272
Amount of fluid filtered by both kidneys per minute?
Around 125mL of urine
273
Amount of fluid filtered by both kidneys per day?
Around 180L of urine produced a day (but not peed out)
274
What structures enter the kidney?
1. Renal Artery
275
What structures exit the kidney?
1. Renal Vein 2. Ureter
276
What are the dimensions of a typical kidney?
10cm long x 5.5cm wide x 3cm thick
277
How much does the kidney weigh?
150g
278
What 5 regions are the ureters found in?
R- lumbar + inguinal, L-lumbar +inguinal, Hypogastric
279
How long are the ureters?
10 inches
280
What are the 2 types of stones formed in the nephron?
1. calcium oxalate 2. calcium phosphate
281
Which type of stone is the weaker and more breakable of the two?
oxalate
282
How to prevent kidney stones?
Drink water
283
What causes pain when passing kidney stones?
Peristalsis forces jagged kidney stones down the smooth ureters
284
What is hydronephrosis?
Kidneys are swollen with fluid
285
In what region of the body is the urinary bladder located?
hypogastric region
286
At what bladder volume does one feel the first urge to pee?
150mL
287
What causes a greater occurence of UTI's in women?
1. Close proximity to the vagina
| 2. Shorter urethra
288
What type of epithelium is in the ureter, urinary bladder, and proximal urethra?
Transitional (no secretions, stretchy)
289
What type of epithelium is in the distal urethra?
Stratified squamous
290
What type of epithelium is in the renal tubule?
Simple cuboidal
291
What is a common cause of hydronephrosis?
Kidney stone blockage
292
What do syphilis and gonorrhea have in common?
They are infections of the urethra
293
What is pyelonephritis?
A kidney infection most commonly caused by a UTI
