A&p 2 - Chapter 25 - Urinary System

Front 1

Glands anterior to the ear, drains into upper cheek

Back 1

parotid gland

Front 2

The major functions of the kidneys are:

Back 2

1. to remove and excrete wastes from the blood
2. to regulate the blood volume
3. to regulate fluid and electrolyte balance and acid-base balance of the blood

Front 3

The urinary system includes:

Back 3

kidneys, ureters, bladder, and urethra

Front 4

The kidneys are partially protected by the:

Back 4

ribs

Front 5

This structure is located on the medial surface of the kidney:

Back 5

renal hilum

Front 6

The renal hilum is where the ______ _______, _______, _____, and ________ enter and exit

Back 6

blood vessels, ureter, nerves, and lymphatics

Front 7

The kidneys are covered by:

Back 7

a fibrous capsule

Front 8

The kidneys are SURROUNDED by a _________ ________ layer and an outer layer of dense connective tissue called the _____ ________

Back 8

perirenal fat layer; renal fascia

Front 9

This occurs when obstruction of urinary flow causes dilation of the intra-renal collecting system:

Back 9

hydronephrosis

Front 10

What does hydronephrosis eventually lead to?

Back 10

kidney damage

Front 11

The kidney has a superficial _____ and a deeper ___________.

Back 11

cortex; medulla

Front 12

The medulla contains what important structures?

Back 12

the medullary or renal pyramids

Front 13

Where does the apex of the renal pyramids point toward? what's another name for the apex?

Back 13

points inward; papilla

Front 14

Urine drains from the papilla of each pyramid into the _______ _______:

Back 14

minor calices

Front 15

The minor calices drain into the:

Back 15

major calices

Front 16

The major calices drain into the _____ ______ which drains into the ________

Back 16

renal pelvis; ureter

Front 17

Which structures in and around the kidneys contain smooth muscle that aid in peristalsis?

Back 17

calices, pelvis, ureter

Front 18

Infection of the entire kidney is called:

Back 18

pyelonephritis

Front 19

Blood is supplied to the kidney by the:

Back 19

renal arteries

Front 20

where do the renal arteries branch from?

Back 20

the aorta

Front 21

How much of the cardiac output do the kidneys receive at rest?

Back 21

25%

Front 22

How much of the cardiac output goes to the renal cortex?

Back 22

>90%

Front 23

What veins carry the blood away from the kidney? Where do these veins drain into?

Back 23

renal veins; into the IVC

Front 24

These are the structural and functional units of the kidneys that carry out the processes that form urine

Back 24

nephrons

Front 25

How many nephrons are there in each kidney?

Back 25

approximately 1 million

Front 26

Each nephron consists of:

Back 26

a glomerulus and a renal tubule

Front 27

what is the "glomerulus?"

Back 27

a ball of parallel capillaries

Front 28

The renal tubule is made up of what 4 things?

Back 28

glomerular capsule, the proximal convoluted tubule (PCT), the loop of Henle (LOH), and the distal convoluted tubule (DCT)

Front 29

This is the cup-shaped structure that surrounds the glomerulus:

Back 29

the glomerular (Bowman's) capsule

Front 30

How many layers make up the glomerular capsule?

Back 30

2, the parietal layer and the visceral layer

Front 31

The visceral layer is made up of branching epithelial cells called __________ which have many _____ ____

Back 31

podocytes; foot processes

Front 32

The spaces between the podocytes are called:

Back 32

filtration slits

Front 33

The fluid that passes through the capsular space is called:

Back 33

filtrate

Front 34

How long is the renal tubule?

Back 34

about 3 cm in length

Front 35

What does the renal tubule empty into?

Back 35

the collecting duct

Front 36

Is the collecting duct a part of the nephron?

Back 36

no

Front 37

Each _______ _______ receives filtrate from multiple nephrons.

Back 37

collecting duct

Front 38

The collecting ducts run through the __________, emptying at the ________

Back 38

pyramids, papilla

Front 39

All of the glomeruli are located in the:

Back 39

cortex

Front 40

The loops of Henle often extend into the _________

Back 40

medulla

Front 41

Each glomerulus has an _________ and an _________ arteriole.

Back 41

afferent, efferent

Front 42

Is the blood pressure higher or lower in the glomerular capillaries than in most other capillaries?

Back 42

higher

Front 43

How much of the filtrate is reabsorbed in the renal tubule?

Back 43

99%

Front 44

Filtrate passes from the _______ _____ which originate from the _______ arteriole and are closely associated with the renal tubule.

Back 44

peritubular capillaries; efferent

Front 45

What is the name of the vessels seen along the juxtamedullary nephrons (instead of peritubular capillaries)?

Back 45

vasa recta

Front 46

What do the vasa recta do?

Back 46

they concentrate the urine

Front 47

What do the afferent arterioles do for the glomerulus?

Back 47

they protect the glomerulus from fluctuations in systemic blood pressure

Front 48

What do the efferent arterioles do for the glomerulus?

Back 48

they maintain the glomerular pressure

Front 49

This is the area where the distal ascending loop of Henle lies adjacent to the afferent arteriole.

Back 49

juxtaglomerular apparatus

Front 50

What does the juxtaglomerular appartus monitor?

Back 50

It monitors solute concentration in the filtrate and blood pressure in the afferent arteriole and regulates blood flow into the glomerulus

Front 51

This separates the blood and capsular space:

Back 51

filtration membrane

Front 52

What does the filtration membrane consist of?

Back 52

1. fenestrated endothelial cells of the glomerular capillaries
2. the visceral layer of the glomerular capsule
3. the basement membrane in between

Front 53

True or false: Formed elements and proteins can easily pass through the filtration membrane.

Back 53

false

Front 54

What easily passes through the filtration membrane?

Back 54

water and smaller molecules

Front 55

How much blood flows through the kidneys per minute?

Back 55

1200 mL

Front 56

How much plasma flows through the kidneys per minute?

Back 56

650 mL/min

Front 57

How much filtrate passes into the renal tubules?

Back 57

120-125ml/min

Front 58

What is filtrate?

Back 58

the plasma minus the proteins

Front 59

What is the name of filtrate that has entered the collecting duct?

Back 59

urine

Front 60

Are the things in the filtrate needed by the body?

Back 60

no

Front 61

How much of the filtrate is lost as urine?

Back 61

Less than 1%

Front 62

Urine production involves 3 major processes:

Back 62

glomerular filtration, tubular reabsorption, and tubular secretion

Front 63

During glomerular filtration, what forces fluids and solutes through the filtration membrane?

Back 63

hydrostatic pressure

Front 64

What is the glomerular pressure in comparison to other capillaries?

Back 64

55 mmHg in the glomerulus

18 mmHg in other capillaries

Front 65

Between glomerular capillaries and other capillaries, which are more permeable?

Back 65

glomerular capillaries

Front 66

If there is protein in the urine, what does this indicate?

Back 66

that there is damage to the filtration membrane

Front 67

what is the glomerular hydrostatic pressure opposed by?

Back 67

the colloid osmotic pressure of the glomerular blood and the capsule hydrostatic pressure

Front 68

What is the net filtration pressure usually?

Back 68

10 mmHg

Front 69

What does GFR stand for?

Back 69

glomerular filtration rate

Front 70

what is the GFR?

Back 70

the volume of filtrate formed each minute by all the glomeruli of both kidneys combined

Front 71

What 3 things influence the glomerular filtration rate?

Back 71

1. total surface area available for filtration
2. filtration membrane permeability
3. the net filtration pressure

Front 72

Is the GFR inversely or directly related to the NFP?

Back 72

directly

Front 73

What happens to filtration when there has been an 18% drop (or 10mmHg drop) in glomerular pressue?

Back 73

filtration stops

Front 74

Does the GFR remain relatively the same or does it fluctuate constantly?

Back 74

Remains relatively the same

Front 75

The GFR is regulated by what two mechanisms?

Back 75

intrinsic and extrinsic

Front 76

Give another name for "intrinsic mechanisms":

Back 76

renal autoregulation

Front 77

What does the kindey do during renal autoregulation?

Back 77

it adjusts its own resistance to keep glomerular pressure constant

Front 78

Are the myogenic mechanisms and the tubuloglomerular feedback mechanisms intrinsic or extrinsic?

Back 78

intrinsic

Front 79

Explain how the myogenic mechanism effects the afferent arterioles:

Back 79

increase in system blood pressure ----> afferent arterioles constrict

decrease in system blood pressure----> afferent arterioles dilate

Front 80

What is the tubuloglomerular feedback mechanism directed by?

Back 80

the juxtaglomerular appartus

Front 81

What does the macula densa do?

Back 81

monitors the NaCl concentration of the filtrate and regulates the diameter of the afferent arteriole

Front 82

The intrinsic mechanisms operate between a MAP of _____ and _____ mmHg

Back 82

80 and 180 mmHg

Front 83

The extrinsic mechanisms include what two systems? what are these systems trying to regulate?

Back 83

the nervous and endocrine system

maintenance of a constant systemic BP

Front 84

Sympathetic stimulation (associated w/extrinsic controls) does what to the BP? the afferent arteriole? the glomerular pressure?

Back 84

increases BP

constricts afferent arteriole

decreases glomerular pressure

Front 85

Explain how the renin-angiotensin mechanisms works:

Back 85

when renin is released from the granular cells of the JGA, it leads to the formation of angiotensin II, which is a potent vasocontrictor and can increase blood volume

Front 86

The formation of angiotensin II does what to blood volume? systemic blood pressure?

Back 86

increase; increase

Front 87

Renin is released during what 3 occurances?

Back 87

1. MAP <80 mmHg
2. decrease GFR (detected by the JGA)
3. direct stimulation from sympathetic nerves

Front 88

What is the term for low urine output?

Back 88

oliguria

Front 89

Anuria is defined as:

Back 89

urine output <50mL/day

Front 90

Tubular reabsorption involves the passage of substances from the filtrate through the ______ and _______ membranes of the _______ _______ cells and the _________ cells of the peritubular capillaries

Back 90

luminal and basolateral membranes

tubular epithelial cells and endothelial cells

Front 91

How much of the nutrients are reabsorbed during tubular reabsorption?

Back 91

virtually all of it

Front 92

During tubular reabsorption, water and electrolyte reabsorption is regulated by:

Back 92

hormones

Front 93

Most reabsorption is driven by the _____ ______ of _____ through the basolateral membrane.

Back 93

active transport of sodium

Front 94

True or false: water passively follows sodium.

Back 94

true

Front 95

There are specific ______ ______ for most solutes.

Back 95

carrier proteins

Front 96

When carrier proteins are saturated, the excess solute is passed in the _______

Back 96

urine (e.g. glucose in diabetes)

Front 97

The maximum amount of a substance that can be reabsorbed per minute is called the:

Back 97

transport maximum

Front 98

Give an example of a substance that is not need by the body, and is therefore, not reabsorbed.

Back 98

creatinine

Front 99

Is it possible for some substances to be reabsorbed, even when they are not needed by the body. If yes, what type of substances are these?

Back 99

yes, lipid soluble substances such as toxins or drugs

Front 100

Where does most reabsorption occur?

Back 100

in the PCT or proximal convoluted tubule

Front 101

The DCT and collecting duct are influenced by what two hormones?

Back 101

ADH and aldosterone

Front 102

What does ADH stand for?

Back 102

anti-diuretic hormone

Front 103

Where is ADH released?

Back 103

in the pituitary gland

Front 104

What does ADH do to the DCT and collecting duct?

Back 104

causes increased reabsorption and decreases urine production

Front 105

Where is aldosterone produced?

Back 105

in the adrenal cortex

Front 106

What does aldosterone do to the DCT and collecting duct?

Back 106

causes increased reabsorption of sodium and water; also causes increased secretion of potassium into the filtrate

Front 107

What is happening during tubular secretion?

Back 107

substances are passing from the peritubular capillaries, through the tubular epithelium, into the filtrate. Other substances are manufactured by the tubular epithelium and secreted.

Front 108

Tubular secretion most often occurs where?

Back 108

in the PCT

Front 109

Tubular secretion is important for what 4 reasons?

Back 109

1. substances which are tightly bound to plasma proteins and are not filtered.
2. waste substances which were reabsorbed in the PCT
3. Potassium, since it is almost completely reabsorbed in the PCT
4. pH control (secretion of H+ and HCO3-)

Front 110

Kidneys regulate the _________ of the plasma

Back 110

osmolality

Front 111

What is osmolality?

Back 111

the total concentration of solute particles

Front 112

What is the osmolality of the plasma usually?

Back 112

approximately 300 mOsm/liter

Front 113

These create an osmotic gradient in the renal medulla

Back 113

countercurrent mechanisms

Front 114

What is the osmolality at the papilla? -caused by the countercurrent mechanisms

Back 114

1200 mOsm/L

Front 115

Urine can be diluted to about _____ mOsm/L

Back 115

70

Front 116

What does ADH do to diuresis and to the urine?

Back 116

inhibits diuresis (urine output)

concentrates the urine (max 1200 mOsm/L)

Front 117

When would increased plasma osmolality occur?

Back 117

during dehydration

Front 118

What does increased plasma osmolality do to ADH?

Back 118

causes increased release of ADH

Front 119

When would decreased plasma osmolality occur?

Back 119

from water excess

Front 120

What does decreased plasma osmolality do to ADH?

Back 120

causes decreased output of ADH

Front 121

These are chemicals which increase urine output:

Back 121

diuretics

Front 122

These are molecules which are not reabsorbed by the renal tubule. They carry water out with them

Back 122

osmotic diuretics

Front 123

Most diuretics block the reabsorption of _______, which is lost in the urine along with water

Back 123

sodium

Front 124

________ ________ refers to the volume of plasma that is cleared of a specific substance in a given time (usually 1 minute)

Back 124

renal clearance

Front 125

The clearance of _________ can be measured and used to estimate the GFR, since it is not reabsorbed

Back 125

creatinine

Front 126

If the clearance value for a substance is MORE/LESS than the GFR, then some of the substance is being reabsorbed

Back 126

LESS

Front 127

If the clearance value is LESS/GREATER than the GFR, then some of the substance is being secreted

Back 127

GREATER

Front 128

A clearance value of zero indicates the substance is _____ ________

Back 128

completely reabsorbed

Front 129

The color of urine is due to:

Back 129

urochrome

Front 130

Urochrome is a pigment resulting from the destruction of _______

Back 130

hemoglobin

Front 131

Usually, the more concentrated the urine, the lighter/darker the color

Back 131

darker

Front 132

What is the average pH of urine? How far can the pH vary?

Back 132

6.0

4.5-8.0

Front 133

This is a measurement of density:

Back 133

the specific gravity (SG)

Front 134

Distilled water has an SG of _____

Back 134

1.0

Front 135

Urine has an SG of _____ to ______

Back 135

1.001 to 1.035

Front 136

A high urine SG indicates what?

Back 136

concentrated urine and dehydration

Front 137

The largest solute component of urine is ______

Back 137

urea

Front 138

What does urea contain?

Back 138

nitrogen released by the breakdown of amino acids

Front 139

_____ ____ comes from the breakdown of nucleic acids.

Back 139

uric acid

Front 140

_________ comes from the breakdown of skeletal muscle tissue.

Back 140

creatinine

Front 141

An increased concentration of specific solutes, or the presence of abnormal substances, may indicate :

Back 141

pathology

Front 142

__________indicates hyperglycemia, usually due to diabetes

Back 142

glucose

Front 143

__________ may indicate glomerular damage or hypertension

Back 143

proteins

Front 144

Free __________ indicates some form of hemolysis.

Back 144

hemoglobin

Front 145

__________ indicates liver disease or bile duct obstruction

Back 145

Bilirubin

Front 146

_________ could indicate glomerular damage, but are usually due to urinary tract bleeding

Back 146

RBC's

Front 147

What causes urinary tract bleeding?

Back 147

trauma, stones, infection, neoplasm

Front 148

_______ indicate urinary tract infection (UTI)

Back 148

WBC's

Front 149

What's another name for chronic renal disease?

Back 149

chronic kidney disease (CKD)

Front 150

CKD refers to a gradual loss of kidney function, demonstrated by:

Back 150

1) a GFR < 60 ml/min.
2) a GFR > 60 ml/min. with signs of kidney damage (eg. proteinuria)

Front 151

Patients have decreased filtrate formation with the accumulation of:

Back 151

nitrogenous wastes (urea and creatinine) and metabolic acidosis

Front 152

When the GFR is < 15 ml/min, it is referred to as:

Back 152

chronic renal failure (CRF) or end-stage renal disease (ESRD)

Front 153

CRF and ESRD require _____ or _______for survival:

Back 153

dialysis or transplant

Front 154

Leading causes of CDK are:

Back 154

diabetes, hypertension, and atherosclerosis

Front 155

___________ involves diffusion of waste molecules across a semipermeable membrane

Back 155

hemodialysis

Front 156

Ureters obliquely through the posterior bladder wall, which acts to create a one-way valve, referred to as the :

Back 156

ureterovesical junction

Front 157

Ureters are lined with ________ epithelium and move urine by ___________

Back 157

transitional; peristalsis

Front 158

Substances can precipitate and crystallize in the calyces and renal pelvis producing :

Back 158

renal calculi or kidney stones

Front 159

How do kidney stones cause pain in the flank and groin area?

Back 159

they move distally and obstruct the ureter

Front 160

The bladder is just posterior to the :

Back 160

pubis

Front 161

In males the neck of the bladder and the proximal urethra are surrounded by the :

Back 161

prostate

Front 162

In females the bladder and urethra are just anterior to the

Back 162

vagina

Front 163

The ureteral and urethral openings form a triangular region at the base of the bladder, called the:

Back 163

trigone

Front 164

The bladder is lined with ________ epithelium and has ___ layers of smooth muscle

Back 164

transitional; 3

Front 165

A moderately full bladder contains about _______ ml

Back 165

500

Front 166

The maximum capacity of the bladder is about:

Back 166

800-1000mL

Front 167

The ______ _______ ________ a thickening of the smooth muscle at the bladder-urethra (vesicourethral) junction

Back 167

internal urethral sphincter

Front 168

How is the internal urethral sphincter controlled?

Back 168

It is involuntary and is opened by contraction and closed by relaxation

Front 169

The _______ ______ ______ is located where the urethra passes through the urogenital diaphragm

Back 169

external urethral sphincter

Front 170

How is the external urethral sphincter controlled?

Back 170

It is made of skeletal muscle so it is voluntarily controlled

Front 171

The female urethra is about ____ in length:

Back 171

4cm

Front 172

The male urethra is about ______ in length

Back 172

20cm

Front 173

The male urethra has 3 portions:

Back 173

1) the prostatic urethra passes through the prostatee
2) the membranous urethra passes through the urogenital diaphragm
3) the spongy (or penile) urethra runs through the penis

Front 174

Inflammation of the urethra is called :

Back 174

urethritis

Front 175

Inflammation of the bladder is called:

Back 175

cystitis

Front 176

_____ is urination or voiding

Back 176

micturition

Front 177

The micturition (or voiding) reflex occurs after about _____ of urine has accumulated in the bladder.

Back 177

200ml

Front 178

What happens physiologically during micturition?

Back 178

The stretch receptors initiate a reflex, which causes the bladder to contract and the internal sphincter to open. The external sphincter is controlled voluntarily

Front 179

When does the external sphincter start to work involuntarily?

Back 179

once the bladder holds > 500-600 mL

Front 180

________ is a lack of voluntary control.

Back 180

incontinence

Front 181

______ _______ is the inability to void

Back 181

urinary retention

Front 182

Urinary retention is common after:

Back 182

general or spinal anesthesia

Front 183

By age 80, what is the common GFR?

Back 183

about 60ml/min (50% of normal)

Front 184

Because older people have a lower GFR, what does this mean for drug dosages?

Back 184

They must be reduced