1.1 : Renal Function Flashcards
(101 cards)
1
Q
What are the 4 main components of the Urinary system
A
- kidney
- ureters
- bladder
- urethra
2
Q
The urinary bladder is made up of what tissue?
A
Transitional epithelium
3
Q
What is the functional unit of the kidney
A
Nephron
4
Q
What are the two types of nephron of the kidney
A
- cortical (85%)
- juxtamedullary (15%)
5
Q
This type of nephron, which make up approximately 85% of nephrons, are situated primarily in the cortex of the kidney
A
Cortical nephrons
6
Q
This type of nephron responsible primarily for removal of waste products and reabsorption of nutrients
A
Cortical nephrons
7
Q
This type of nephron have longer loops of Henle that extend deep into the medulla of the kidney
A
Juxtamedullary nephron
8
Q
The primary function of this type of nephron is focused on the concentration of the urine
A
Juxtamedullary nephron
9
Q
This is responsible for clearing waste products selectively from the blood and simultaneously maintaining the body’s essential water and electrolyte balances
A
Nephrons
10
Q
What are the renal functions under the nephron?
A
- renal blood flow
- glomerular filtration
- tubular reabsorption
- tubular secretion
11
Q
The renal blood flow begins by __________
A
(Blood) enters the nephron via afferent arteriole
12
Q
In the renal blood flow, the blood enters the nephron via the _______ arteriole
A
Afferent
13
Q
In the renal blood flow, after the blood passes through the afferent arteriole, it flows through the ________ via _______
A
Glomerulus ; efferent arteriole
14
Q
In the renal blood flow, blood from the efferent arterioles enters the __________ capillaries and _________ (for immediate reabsorption)
A
Peritubular capillaries ; Vasa recta
15
Q
Based on the average size, what is total renal blood flow? (mL/min)
A
1200 mL/min
16
Q
Based on the average size, what is total renal plasma flow? (mL/min)
A
600-700 mL/min
17
Q
The peritubular capillaries surround the _______ and ______ consulates tubules providing for the immediate reabsorption of essential substances from the fluid in the ______________ and final adjustment of the urinary composition in the __________
A
proximal ; distal
18
Q
The vasa recta are located adjacent to the ______________ in ______________
A
ascending & descending loops of Henle ; juxtamedullary nephrons
19
Q
The major exchanges of water and salts take place between the blood and the _______________
A
medullary interstitium
20
Q
The major exchanges of water and salts that take place between the blood and medullary interstitium maintains the ___________ ( necessary for renal conc.)
A
Osmotic gradient
21
Q
The ___________ consists of a coil of approximately eight capillary lobes, the walls of which are referred to as the glomerular filtration barrier
A
Glomerulus
22
Q
The walls of the glomerulus is referred to as the ________
A
Glomerular filtration barrier
23
Q
Where is the glomerulus located at?
A
Bowman capsule
24
Q
What are the factors influencing the filtration process?
A
- cellular structure of the glomerulus
- hydrostatic pressure
- oncotic pressure
- feedback mechanism of RAAS
25
What is the meaning of RAAS
Renin-Angiotensin-Aldosterone-System
26
In the cellular structure of the glomerulus, the plasma filtrate must pass through **three glomerular filtration barrier cellular layers**
- capillary walk membrane
- basement membrane (basal lamina)
- visceral epithelium of the Bowman capsule
27
How does the endothelial cells of the capillary wall of the glomerular differ from other capillaries?
It contains **pores** aka **fenestrated endothelium**
28
T or F
The poorest of the endothelial cells of the capillary wall of the glomerular increases capillary permeability, but do not allow the passage of large molecules in blood cells
True
29
Besides the capillary wall of the glomerulus, the basement membrane also does not allow the passage of large molecules and passes through thin membrane, covering the filtration slits formed by intertwining foot processes called the _____________
Podocytes
30
The glomerular filtration barrier also contains a ____________ that **repels** molecules with a **negative** charge even though they are small enough to pass through the three layers of the barrier
shield of negativity
31
What is the primary protein associated with renal disease that is repelled by the shield of negativity?
Albumin
32
This results from the smaller size of the efferent arterial and the glomerular capillaries, which then enhances filtration.
Hydrostatic pressure
33
This is necessary to overcome the opposition of pressures from the fluid within the Bowman capsule and the oncotic pressure of unfiltered plasma proteins
Glomerular pressure
34
This results from increasing or decreasing the size of the afferent and efferent arterioles and occurs within the juxtaglomerular apparatus which maintains the glomerulus blood pressure
Autoregulatory mechanism
35
_________ of the **afferent arterioles** and __________ of the **efferent arterioles** when **blood pressure drops** prevent a marked **decrease** in blood flowing through the kidney = preventing an increase in the blood level of toxic waste products
Dilation ; constriction
36
An increase in blood pressure result in ___________ of the **afferent arterioles** to prevent **overfiltration** or dames to the glomerulus
Constriction
37
Enumerate the steps in the **Renal blood flow**
1. Enters the **Renal artery**
2. Passes through the **afferent arteriole**
3. Flows thru the **glomerulus**
4. Goes into the **efferent arteriole**
5. Enters the **peritubular capillaries**
6. Enters the **vasa recta**
7. Back to the **renal vein**
38
Enumerate the steps in the **Urinary filtrate flow**
1. Bowman capsule
2. Proximal convoluted tubule
3. Descending loop of Henle
4. Ascending loop of Henle
5. Distal convoluted tubule
6. Collecting duct
7. Renal calyces
8. Ureter
9. Bladder
10. Urethra
39
This regulates the flow of blood to and within the glomerulus
RAAS
40
This responds to **changes in blood pressure** and **plasma sodium content** that are monitored by the **juxtaglomerular apparatus**
RAAS
41
Juxtaglomerular apparatus consists of the:
- juxtaglomerular cells (afferent arteriole)
- macula densa (distal convoluted tubule)
42
**Low plasma sodium** content **decreases water retention** within the circulatory system —> decreased overall blood volume, which results to:
decrease in blood pressure
43
It is an enzyme produced by the **juxtaglomerular cells**, which is secreted and reacts with **Angiotensinogen** to produce **Angiotensin I**
Renin
44
What produces renin?
Juxtaglomerular cells
45
What converts **Angiotensin I** to its active form **Angiotensin II**
Angiotensin-converting enzyme (ACE)
46
What are the ways on how Angiotensin II corrects the renal blood flow?
- vasodilation of AA, constriction of EA
- reabsorption of water (CD) and sodium in the PCT & DCT)
- release of Aldosterone by adrenal cortex to stimulate sodium reabsorption & potassium excretion (DCT)
- release of Antidiureti hormone (ADH) by the hypothalamus to stimulate water reabsorption by (CD)
47
As systemic blood pressure and plasma sodium content **increases**, renin __________
Decreases
48
What are the substances reabsorbed through the **active transport**?
- glucose, amino acids, salts (PCT)
- chloride (PCT)
- sodium (LCT & DCT)
49
What are the substances reabsorbed through the **passive transport**?
- water (PCT, DLoH, CD)
- urea (PCT, ALoH)
- sodium (ALoH)
50
Renal concentration begins where?
Descending and Ascending Loop of Henle
51
In tubular concentration, **water** is **removed** by _________ in the __________
Osmosis ; DLoH
52
In tubular concentration, **sodium (Na)** and **chloride (Cl)** are **reabsorbed** in the _________
ALoH
53
What are the cellular mechanisms involved in tubular reabsorption?
- active transport
- passive transport
54
This cellular mechanism requires to be combined with a **carrier protein** in order for the substance to be reabsorbed
Active transport
55
This cellular mechanism is movement of molecules across a membrane as a result of differences in their concentration (**gradient**) or **electrical potential** on opposite sides of the membrane
Passive transport
56
Passive reabsorption of water takes place in all parts of the nephron except the ________
ALoH (walls are impermeable to water)
57
When the **plasma concentration** of a substance that is normally completely reabsorbed reaches a level that is **abnormally high**, the filtrate concentration exceeds _________
maximal reabsorptive capacity (Tm)
58
The **plasma concentration** at which **active transport stops** is termed as the _________
Renal threshold
59
What is the plasma renal threshold for glucose?
160 - 180 mg/dL
60
T or F
**Glucose appearing in the urine** of a person with a normal blood glucose level is the result of **tubular damage** and not diabetes mellitus.
True
61
**Excessive reabsorption of water** as the filtrate passes through the highly concentrated medulla is prevented by the _________
Water-impermeable walls of ALoH
62
This is the selective reabsorption process of preventing excessive water reabsorption through the aid of the water-impermeable walls of ALoH
Countercurrent mechanism
63
Maintenance of the osmotic gradient is essential for the final concentration of the filtrate when it reaches the _______________
collecting duct
64
This serves to maintain the osmotic gradient of the medulla
Concurrent mechanism
65
This serves to maintain the osmotic gradient of the medulla
Concurrent mechanism
66
Reabsorption depends on __________ in the medulla and the hormone _________ that is released by the **posterior pituitary gland** when the amount of water in the body decreases
Osmotic gradient ; vasopressin (Antidiuretic hormone / ADH)
67
A high level of ADH results in:
- increases permeability
- increased reabsorption of water
- low-volume conc urine
68
Absence of ADH results in:
- renders the walls impermeable to water
- large volume of dilute urine
69
The production of aldosterone is controlled by the ___________
body’s sodium concentration
70
The production of ADH is determined by the state of ___________
Body hydration
71
What is the final determinant or urine volume and concentration?
Chemical balance in the body
72
What will happen to ADH and urine volume if there is an **increase** in body hydration?
- decreased ADH
- increased urine volume
73
What will happen to ADH and urine volume if there is an **decrease* in body hydration?
- increased ADH
- decreased urine volume
74
This involves the **passage of substances** from the blood in the **peritubular capillaries** to the **tubular filtrate**
Tubular secretion
75
This renal function serves the following two major functions:
- **Elimination of waste products** not filtered by the Glomerulus
- **Regulation of acid base balance** through secretion of H ions
Tubular secretion
76
This renal function serves the following two major functions:
- **Elimination of waste products** not filtered by the Glomerulus
- **Regulation of acid base balance** through secretion of H ions
Tubular secretion
77
These are standard tests used to measure the **filtering capacity of the glomeruli**
Clearance tests
78
It measures the rate in mL/min at which the kidneys are able to remove (to clear) a filterable substance from the blood
Clearance tests
79
What are the primary substances used in clearance tests?
- creatinine
- beta 2-microglobulin (B2M)
- cystatin C
- radiotopes
80
T or F
Based on the characteristics of substance to be tested:
Should not be reabsorbed or secreted by the tubules
True
81
Based on the characteristics of substance to be tested:
Substance must be stable for ________ hrs
24 hrs
82
Based on the characteristics of substance to be tested:
Plasma level should be ________
Constant
83
The earliest glomerular filtration tests measured __________ because of its presence in all urine specimens, as well as the existence of routinely used methods of chemical analysis
urea
84
How many percent of urea is reabsorbed?
40%
85
It is a polymer of **fructose** that is an extremely stable substance that is neither reabsorbed nor secreted by the tubules
Inulin
86
It is a test that requires an infused substance
Exogenous procedure
87
It is a suitable test substance is already present in the body
Endogenous procedure
88
The urea clearance test requires a ________ sample
2-hr sample
89
What is the earliest clearance test?
Urea clearance test
90
What is the problem / cons of the urea clearance test?
It is **reabsorbed** by the **tubule**
91
The advantage of this test is that it is extremely **stable** and not reabsorbed
Inulin clearance test
92
The advantage of this test is that it is extremely **stable** and not reabsorbed
Inulin clearance test
93
The disadvantage of this test is that it is **infused** at a **constant rate**
Inulin clearance test
94
The creatinine clearance test requires a ________ hr sample
24 hr sample
95
It is the **endogenous** procedure for evaluating glomerular filtration
Creatinine clearance test
96
One of the disadvantages of the creatinine clearance test is that some creatinine are **secreted** by ____
Tubules
97
T or F
**Diet** can also influence the test results of the creatinine clearance test
True
98
Create clearance test is not reliable when the patient is/has:
- muscle-wasting diseases
- heavy exercises
- supplementing with creatine
99
What is the sample required for renal function tests
Midstream cleancatch urine
100
What is the reference range for creatinine clearance for male?
107-139 mL/min
101
What is the reference range for creatinine clearance for female?
87-107 mL/min
