Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Physiology > renal 3 - filtration > Flashcards

renal 3 - filtration Flashcards

(65 cards)

Start Studying
1
Q

which two processes involve entry into renal lumen

A

glomerular filtration and tubular secretion

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

which two processes involve entry out of the renal lumen

A

tubular reabsorption and excretion of urine

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

formula for amount excreted

A

amount filtered+amount secreted-amount reabsorbed

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

what are the 3 layers of the glomerular capillary

A

fenestrated endothelium
basement membrane
podocytes with filtration slits

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

why cant large proteins or albumin go through filtration (3 reason)

A
  • too large for pores
  • pores&BM are negative, they repel negative proteins
  • podocyte slits remain covered with find semiporous membranes (nephrins podocins)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are nephrins and podocins

A

proteins that determine what can pass through the podocyte slits

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

what is the ultrafiltrate

A

the filtrate that passed through the capillary and has nearly identical composition to the plasma (besides RBC and proteins)

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

what is proteinuria

A

when there is protein in the filtrate

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

what could cause proteinurea

A

issues with nephrins and podocins

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

is net glomerular filtration always positive or negative and why

A

always positive because you are pushing things out into the bowmans space

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

what is PBS and what is its role towards filtration

A

fluid pressure in bowmans space

opposed filtration

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

what is piBS

A

osmotic force due to proteins in bowmans space

BUT ITS 0 because there are no proteins in the bowmans space

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

overall, what is the difference with P and pi

A

P is the fluid pressure

pi is the opposing osmotic force

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

what is PGC and what is its role towards filtration

A

glomerular capillary blood pressure

favors filtration

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

what is piGC and what is its role towards filtration

A

osmotic force due to proteins in plasma

opposing filtration

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

what is the net glomerular filtration pressure

A

PGC-PBS-piGC

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

which direction does PGC go

A

capillary–>bowman

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

which direction does PBS go

A

bowman–>capillary

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

which direction does piGC go

A

bowman–>capillary

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

which direction does piBS go

A

none cause pretty much zero

otherwise it would go towards to bowmans space

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

which has the highest pressure (PBS PGC piBS piGC)

A

PGC

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

what does Glomerular filtration pressure initate

A

urine formation by forcing protein ree filtrate from plasma out of the glomerulus into bowmans space

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

what is filtration fraction (and the %)

A

only 20% of the plasma entering the afferent arteriole is iltered

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

what % of the filtered volume is excreted

A

less than 1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what % of the filtered volume is reabsorbed
19% (20% filtered, 1% remains)
26
what is flomerular filtration rate (GFR)
the volume of fluid filtered from the glomerulus into the bowmans space per unit time
27
what is GFR for human
125mL/min 180L/day for 70kg man
28
which 4 factors influence GFR
- net glomerular filtration pressure - permeability of corpuscular membrane - surface area for filtration - neural and endocrine control
29
how does GFR change with changes in arterial pressure or renal blood flow?
it remains constant so that you don't damage the nephrons
30
how do you do autoregulation of GFR
change renal blood vessel resistance (compensate for changes in BP)
31
how do you change the arteriol resistance
myogenic response of afferent arteriole (smooth muscle) | or the tubuloglomerular feedback effect
32
what is the tubuloglomerular feedback effect
increase flow causes constriction of the afferent arteriol to reduce GFR
33
how is the tubuloglomerular feedback effect regulated
- paracrine actions of the juxtaglomerular apparatus (cells close to glomerulus) - paracrine control of afferent arteriole resistance
34
what range of blood pressures does autoregulation maintain a nearly constrant GFR
80-180mm Hg
35
what is mean arteriol blood pressure formula
2/3 diastolic pressure + 1/3 systolic pressure
36
why does autoregulation of glomerular filtration rate take place in a small range of blood pressures
it doesnt | it is a wide range so that your body can handle a large fluctuation of blood pressure
37
where does most resistance change occur
afferent arterioles
38
what happens (to GFR, capillary BP and blood flow) when you increase resistance in afferent arteriole
decrease GFR decrease capillary BP decrease renal blood flow increase flow to other organs
39
what happens (to GFR, capillary BP and blood flow) when you increase resistance in efferent arteriole
increase GFR increase capillary BP decrease renal blood flow increase flow to other organs
40
what are two ways to decrease GFR
constrict afferent arteriole | dilate efferent arteriole
41
what are two ways to increase GFR
dilate afferent arteriole | constrict efferent arteriole
42
what is myogenic response of GFR regulation
similar to autoregulation in other systemic arterioles
43
what does autoregulation mean
mean arteriole pressure is fluctuating but this helps keep it constant
44
what is a role of the juxtaglomerular apparatus
tubuloglomerular feedback
45
what does increased tubular flow cause to afferent arteriole and why
constrict afferent to reduce GFR
46
how is tubuloglomerular feedback regulated
paracrine control of afferent arterioles by the juxtaglomerular apparatus
47
how does afferent smooth muscle react with an increase in BP
smooth muscle cells in the wall of the arteriole are stretched and respond by contracting to resist the pressure, resulting in little change in flow
48
how does afferent smooth muscle react with an decrease in BP
smooth muscle cells relax to lower resistance, allowing a continued blood flow
49
what kind of GFR regulation is not autoregulated
hormones and autonomic neurons
50
how do hormones and autonomic neurons work
not autoregulate | they change resistance in arterioles
51
what are the components of the juxtaglomerular apparatus
macula densa and juxtaglomerular cells
52
what/where are the macula densa
cells on the wall of the distal convoluted tubule
53
what do macula densa sense
can sense increased fluid flow through distal tubule (senses [Na+] and [Cl-])
54
what do macula densa secrete and what does this cause
secrete vasoactive compounds with paracrine effects on afferent arteriol resistance this signals to JG cells (controls GFR)
55
what do juxtaglomerular cells do
secrete renin
56
where are juxtaglomerular cells
on the wall of the afferent arteriole
57
what are granular cells
juxtaglomerular cells
58
what are mesangial cells
similar to smooth muscle, help with muscle contraction
59
are mesangial cells part of the juxtaglomerular apparatus
noooo
60
what 4 factors control GFR
- myogenic arteriole reflex - neuro-endocrine input on arterioles - paracrine effects of macula densa - mesangial cells
61
what happens with contraction of mesangial cells (surface area and GFR)
reduces surface area of glomerular capillaries | GFR decreased
62
what is the definition of filtered load
total amount of non protein or non protein bound surface filtered into bowman's space
63
what is the formula of filtered load
GFRx[substance in plasma] | not protein, its stuff like glucose
64
what happens when substance excreted in urine
reabsorption | less is released than in the load
65
what happens when substance excreted in urine>filtered load
secretion | more is excreted than in the load

Physiology (32 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions