Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

321 - Physiology > Lecture 38 - Glomerular Filtration > Flashcards

Lecture 38 - Glomerular Filtration Flashcards

1
Q

The three processes involving the nephrons, collecting ducts, and their blood supply formation in urine formation are

A

Glomerular filtration, tubular reabsorption, and tubular secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

An _____________ of urine is formed in the cortex and is modified during its course through the medulla

A

Ultrafiltrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What drives filtration?

A

The structures within the cortex, primarily the glomeruli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The tubules within the medulla are responsible for

A

Reabsorbing, excreting, and concentrating the urinary filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Our kidneys filter ________ of blood every minute, which works out to be 45 gallons of blood per day

A

Half a cup of blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Kidneys filter all blood in your body ________ times a day

A

50 - this keeps blood’s components stable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How much blood volume do kidneys Reabsorb?

A

99%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is ultrafiltration

A

The first of 3 processes by which metabolic wastes are separated from the blood and urine is formed. Nonspecific filtration of the blood under high pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where does ultrafiltration occur

A

Renal corpuscle of the nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What facilitates ultrafiltration?

A

The ultrastructure of the glomerulus and Bowman’s capsule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The glomerulus is made up of

A

Many capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Blood flows into capillaries through a ___________ & leaves through ________________

A

Wider afferent arteriole, narrower efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The change in diameter of arteriole going/leaving the glomerulus maintain

A

A high filtration pressure which is essential for filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What forces molecules through the glomerular filtration barrier

A

High filtration pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the glomerular filtration barrier responsible for

A

Selectively filtering the blood forming the glomerular filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The Bowman’s capsule surrounds the

A

Capillaries of the glomerulus and has 2 layers of cells separated by the urinary space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

The inner cells of bowman’s capsule are called

A

Podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Podocytes have cellular extensions called _______

A

Pedicels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What do pedicels wrap around

A

Blood vessels of the glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Where is filtrate collected before entering the proximal tubule

A

Urinary space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The major players of the glomerular filtration barrier include

A

Endothelium, glomerular basement membrane, and podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Glomerular endothelial cells are characterized by

A

Numerous fenestrations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Glomerular endothelial cells have fenestrations to allow

A

Water & non-cellular components of blood to pass through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Glomerular endothelial cells act as a barrier to

A

Cells in the blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The glomerular basement membrane is a product of fusion of the basement membranes produced by

A

Endothelial cells and podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What secretes proteins to make up the basement membrane

A

Podocytes and endothelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the main barrier to proteins

A

Glomerular Basement membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Does the glomerular basement membrane have a lower permeability to anions or cations

A

Anions ! This allows for further selective filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Podocytes are what kind of cell

A

Epithelial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What do podocytes do

A
  • provides structural & functional stability to the glomerulus
  • vital part of glomerular filtration barrier
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Podocytes are located on

A

The opposite side of capillary lumen and cover the outer part of the glomerular basement membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Podocyte cell bodies and major processes float in

A

Bowman’s space in primary urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Podocytes have numerous

A

Processes, similar to tentacles that surround the capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Each podocyte process has many

A

Smaller processes (foot processes or pedicels) that attach to the underlying basement membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

The foot proceses of podocytes interdigitate with

A

Foot processes of adjacent podocytes (let them dogs out)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

The space between the foot processes forms the

A

Slit diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

The slit diaphragm is a

A

Molecular sieve, and it provides an additional filtration barrier based mainly on size exclusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Blood that is travelling through the capillary is selectively filtered across

A

The glomerular filtration barrier to form an ultrafiltrate of the plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

This filtration barrier permits passage of small and some medium sized molecules while blocking the passage of

A

Large molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

The glomerular filtrate is called an ultrafiltrate of plasma because

A

The larger components (platelets and blood cells) and not filtered

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Glomerular filtrate is similar to plasma and interstitial fluid, except that it has

A

A lower protein concentration than either of them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Glomerular filtrate is similar to plasma and interstitial fluid, except that

A

It has a lower protein concentration than either of them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Glomerular filtration barrier filter molecules bigger than

A

7000 DA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Small molecules with a molecular weight <7000 Da are filtered without restriction. These include:

A

Water
Cl
Creatinine
Urea
Uric acid and Phosphate are filtered in isotonic levels (same conc as plasma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Larger molecules with a molecular weight > 7000 Da such as myoglobin are filtered

A

Less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Plasma proteins with molecular weights up to 70 000 Da are heavily restricted from

A

Passing through the glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

However, small amounts of albumin do make it across the membrane. These are completely reabsorbed in

A

The proximal tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Normal filtrate is basically ______ free

A

Protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

Glomerular filtration rate (GFR) is the measure that describes

A

The total amount of filtrate formed by all the renal corpuscles in both kidneys per minute

50
Q

GFR is influenced by

A

Both the hydrostatic pressure and the colloid osmotic pressure (oncotic pressure) on either side of the capillary membrane of the glomerulus

51
Q

The blood inside the glomerulus creates a

A

Hydrostatic pressure which is the force to move fluid out of the glomerulus into the lumen of Bowman’s capsule. Thus, net fluid movement will be into the Bowman’s capsule

52
Q

Glomerular filtration will occur when the

A

Glomerular hydrostatic pressure exceeds the luminal hydrostatic pressure of the Bowman’s capsule. Thus, net fluid movement will be into the Bowman’s capsule

53
Q

Increased blood volume with its higher blood pressure will go into the afferent arteriole and into the glomerulus, resulting in

A

Increased GFR

54
Q

Low blood volume due to dehydration will cause a

A

Decreased GFR

55
Q

Other than blood pressure, what can impact GFR

A

Pressure changes within the afferent and efferent arteriole that go into and out of the glomerulus

56
Q

Arteriole pressure can be varied by

A

Changes in the diameter of the afferent or efferent arteriole

57
Q

Dilation of the afferent arteriole increases the blood flow to the glomerulus, which in turn increases

A

The pressure and potential for filtration

58
Q

Constriction of the efferent arteriole increases

A

Glomerular pressure

59
Q

The Bowman’s capsule space exerts hydrostatic pressure of its own that pushes

A

Against the glomerulus

60
Q

Increased Bowman’s capsule hydrostatic pressure will

A

Decrease GFR

61
Q

Decreased Bowman’s capsule hydrostatic pressure will

A

Increase GFR

62
Q

What could cause bowman’s capsule hydrostatic pressure to rise?

A

Ureter obstruction to the flow of urine that gradually causes a fluid build up in the nephrons.

63
Q

The renal corpuscle filters the blood to create a filtrate that differs from blood mainly

A

By the absence of cells and large proteins

64
Q

From the renal corpuscle to the ends of collecting ducts, the filtrate of forming urine is undergoing

A

Modification through secretion and reabsorption before true urine is produced

65
Q

Tubular reabsoprtion involves transport of water and solute from

A

Tubular fluid to peritublar capillaries

66
Q

Tubular secretion is associated with

A

Transport of solute from peritubular capillaries to the tubular fluid

67
Q

Selective reabsorption is

A

The second of 3 processes by which blood is filtered and urine formed. When filtrate passes through nephron, much of its contents are reabsorbed into the body

68
Q

Reabsorption is a finely tuned processes that is altered to

A

Maintain homeostasis of blood volume, blood pressure, plasma osmolarity, and blood ph

69
Q

Reabsorbed fluids, ions, and molecules are returned to the bloodstream, through

A

The peritubular capillaries and are not excreted as urine

70
Q

Substances important to body function, such as Na+, glucose, and amino acids enter tubular fluid by

A

Filtration at the glomerulus

71
Q

Because of Na+, glucose, and amino acids’ relatively small molecular size, they pass easily through

A

The glomerular membrane, and their concentration in the glomerular filtrate is about equal to their concentration in plasma

72
Q

The majority of selective reabsorption occurs in

A

The proximal convoluted tubule, which extends from the Bowman’s capsule

73
Q

The proximal tubule is located in the

A

Cortex

74
Q

The proximal tubule selectively reabsorbs

A

Useful substances (electrolytes, nutrients, and fluid) via multiple mechanisms of transport

75
Q

The proximal tubule is composed of

A

A simple columnar epithelium joined together by tight junctions

76
Q

The apical brush border is a

A

Characteristic and distinguishing feature of the proximal tubule

77
Q

The luminal surface of the epithelial cells of this segment of the nephron (proximal tubule) is covered with

A

Densely packed microvilli forming a border readily visible under the light microscope giving the brush border its name

78
Q

The microvilli greatly increase the

A

Luminal surface of the cells, presumably facilitating their re absorptive function

79
Q

The cytoplasm of the cells of proximal tubules are densely packed with

A

Mitochondria

80
Q

Mitochondria of proximal tubule epithelial cells are needed to

A

Supply the energy for the active transport of sodium ions out of the cells to create a concentration gradient

81
Q

In order for Na+, glucose, and amino acids from the tubular fluid to be returned to the blood, energy is supplied by

A

The Na+/K+-ATPase pump (sodium pump) on the basal and lateral surfaces of the tubular epithelial cells

82
Q

Na+K+-ATPases constantly pump

A

Na+ out of the cell, maintaining a strong electrochemical gradient for Na+ to move into the cells from the tubular lumen

83
Q

Sodium is actively pumped into the interstitial spaces between cells and diffuses down

A

It’s concentration gradient into the peritubular capillary

84
Q

On the apical surface of proximal tubule, a Na+/glucose cotransporter protein assists

A

Both Na+ and glucose movement into the cell

85
Q

The cotransporter moves glucose into the cell against

A

It’s concentration gradient, where it then diffuses across the basal membrane by facilitated diffusion into the interstitial space and from there into peritubular capillaries

86
Q

Na+ moves down the electrochemical gradient created by

A

The basal membranes Na+/K+ ATPases

87
Q

Simultaneous transport of two or more compounds on the same carrier in the same direction is called

A

Cotransport. Ex Na+/glucose

88
Q

Water will follow Na+/glucose passively to

A

Maintain an isotonic fluid environment inside the capillary

89
Q

Movement of water into the peritubular capillaries is influenced mainly by

A

Osmolarity and concentration gradients

90
Q

The proximal tubules secrete retained organic solutes and drugs directly into the urine to

A

Remove substances that are not easily filtered. This achieves waste removal, disposes of end products that have been reabsorbed passively, such as urea and uric acid, and acid-based balance

91
Q

The tubular secretion of H+ from the blood into the tubular fluid is involved in

A

Blood pH regulation

92
Q

The typical pH of urine is about

A

6.0, much lower than blood which is 7.35-7.45

93
Q

The secretion of H+ is mainly a result of

A

The Na/H exchanger, which is an antiporter in the apical membrane

94
Q

Energy for H+ secretion is provided by

A

The Na/K ATPase in the basolateral membrane. This allows it to drive H+ against its concentration gradient

95
Q

Urine is formed via the three processes of

A

Filtration, reabsorption, and secretion

96
Q

Urine leaves the kidney through

A

The ureter & is stored in bladder before being removed through the urethra

97
Q

Right before peeing, urine is only approximately ______ % of the originally filtered volume

A

1

98
Q

Urine is made up of highly diluted amounts of

A

Urea, creatinine, and variable concentrations of ions

99
Q

Do the kidneys reabsorb creatinine

A

No

100
Q

A build up of creatinine in the blood can be a sign of

A

Impaired kidney function. This can lead to chronic kidney disease

101
Q

Kidney diseases are conditions that

A

Incapacitate the kidney’s ability to filter waste products from the blood

102
Q

Individuals with kidney diseases will demonstrate a(n) ___________________GFR

A

Decreased

103
Q

If untreated, kidney diseases can lead to

A

Kidney failure

104
Q

What can be used as an indicator of kidney disease

A

Kidneys prevent the excretion of blood cells and proteins during ultrafiltration as well as glucose (selective reabsorption). Presence of these materials in urine can be used as indicator of disease

105
Q

The presence of glucose in urine is a common indicator of

A

Diabetes (high blood glucose = incomplete reabsorption)

106
Q

The presence of blood in urine can indicate

A

A variety of diseases, including certain infections and cancer

107
Q

High quantities of protein in urine may indicate

A

Disease or hormonal conditions (hCG= pregnancy)

108
Q

Under normal conditions, albumins cannot be filtered into the

A

Bowman’s capsule

109
Q

In certain kidney diseases, the basement membrane may be damaged which makes it

A

Leaky to proteins

110
Q

Many drugs pass through the body into urine and can be

A

Detected (ie performance enhancing drugs)

111
Q

Glomerular diseases are a leading cause of

A

Chronic kidney disease (CKD) in dogs and less often in cats

112
Q

In dogs, the two major causes of proteinuric renal disease are

A

Glomerular nephritis and renal amyloidosis

113
Q

Glomerular nephritis

A

Inflammation of the glomeruli

114
Q

Renal amyloidosis

A

Deposition of amyloid fibrils in glomeruli, vessels, and/or interstitium

115
Q

If glomeruli are damaged, what leaks into urine

A

Protein from the blood (check protein to creatinine ratio)

116
Q

How to determine the specific glomerular disease present in any animal

A

Renal biopsy

117
Q

Human glomerular disease is routinely defined following

A

-Examination light microscopic sections with a specific panel of histochemical stains
-Immunofluorescence to detect presence of immunoglobulins and complement proteins
-Transmission electron microscopy

118
Q

Clinical signs associated with urinary protein loss are usually non specific:

A

Mild: weight loss, lethargy
Severe: edema, abdominal fluid collection
Extensive: renal failure, anorexia, Nausea, and vomiting

119
Q

Most important treatment for glomerular diseases is

A

Identification and correction of any underlying disease processes

120
Q

For glomerulonephritis, immunosuppressive drugs, antiplatelet therapy, and supportive therapy are done to

A

Decrease hypertension, edema, and the tendency for thromboembolism

321 - Physiology (52 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions