Brainscape's Knowledge GenomeTM

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


See full index

AP II > Exam 4 - Renal > Flashcards

Exam 4 - Renal Flashcards

1
Q

In to something

A

Afferent

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

Out of something

A

Efferent

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

PCT

A

Proximal convoluted tubule

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

LOH

A

Loop of Henle

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

DCT –

A

Distal convoluted tubule

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

JGA –

A

Juxtaglomerular apparatus

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

Functions of the Kidneys

HELPS TO…

A

HELPS TO…

1) Regulate blood ionic composition
2) Regulate blood pH
3) Regulate blood volume
4) Regulate blood pressure
5) Maintain blood osmolarity
6) Produce certain hormones
7) Regulate blood glucose levels
8) Excrete wastes and foreign substances

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

Kidney Functions:

HELPS TO…

Regulate blood ionic composition by?

A

—Helps to regulate blood levels of ions like sodium (Na+), potassium (K+), calcium (Ca2+), chloride (Cl-), and phosphate (HPO42-)

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

Kidney Functions:

HELPS TO…

Regulate blood pH by?

A

—Kidneys excrete variable amount of hydrogen ions (H+) into urine and conserve bicarbonate ions (HCO3-); bicarb is important buffer of H+

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

Kidney Functions:

HELPS TO…

Regulate blood pressure by?

A

Kidneys excrete enzyme renin, this activates renin-angiotensin-aldosterone pathway; increased renin = increased blood pressure

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

Kidney Functions:

HELPS TO…

Excrete wastes and foreign substances by?

A

By forming urine, kidneys help body to get rid of wastes

  • –Ammonia and urea- from deamination of amino acids
  • –Bilirubin- catabolism of hemoglobin
  • –Creatinine- breakdown of creatine phosphate in muscle fibers
  • –Uric acid- catabolism of nucleic acids

Foreign substances

  • –From diet
  • –Drugs
  • –Environmental toxins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Kidney Functions:

HELPS TO…

Maintain blood osmolarity by?

A

Separately regulates loss of water and loss of solutes in urine, kidneys maintain relatively constant osmolarity close to 300mOsm/liter

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

Kidney Functions:

HELPS TO…

Produce certain hormones by?

A

Kidneys produce the hormones calcitriol (active form of Vitamin D) erythropoietin (stimulates production of RBC’s) and renin (hormone/enzyme)

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

Kidney Functions:

HELPS TO…

Regulate blood glucose levels by?

A

Like the liver, the kidneys can use amino acid glutamine in gluconeogenesis, which can then release new glucose into the blood stream to help maintain normal level

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

Right kidney is slightly lower than left – Why?

A

Liver

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

Anatomy of Kidneys:

Located in ?

Anatomically between…

Partially protected by the?

A

retroperitoneal space

…last thoracic and 3rd lumbar vertebrae

11th and 12th ribs

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

Anatomy of Kidneys:

Concave medial border (Hilum) faces the…

A

spinal column

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

Anatomy of Kidneys:

_____ (Hilum) faces the spinal column

A

Concave medial border

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

Anatomy of Kidneys:

_____ (Hilum) faces the spinal column

A

Concave medial border

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

look at anatomy of kidneys and position of kidneys slides

A

well done

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

External Anatomy of the Kidney:

Three External layers?

A

Renal fascia- Outermost layer
Dense connective tissue anchors kidney to surrounding structure and retroperitoneal wall

Adipose capsule- Middle layer
Fatty tissue surrounding renal capsule, protection and holds kidney in place in cavity (aka “renal fat pad”)

Renal capsule- Innermost layer
Smooth, transparent connective tissue covering that is continuous with ureters; helps maintain shape of kidney and offers protection

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

External Anatomy of the Kidney:

Dense connective tissue anchors kidney to surrounding structure and retroperitoneal wall

A

Renal fascia- Outermost layer

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

External Anatomy of the Kidney:

Fatty tissue surrounding renal capsule, protection and holds kidney in place in cavity (aka “renal fat pad”)

A

Adipose capsule- Middle layer

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

External Anatomy of the Kidney:

Smooth, transparent connective tissue covering that is continuous with ureters; helps maintain shape of kidney and offers protection

A

Renal capsule- Innermost layer

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

External layers of the kidney, outermost to innermost:

A

Renal fascia- Outermost layer
Adipose capsule- Middle layer
Renal capsule- Innermost layer

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

External Anatomy of the kidney, outermost to innermost from PHOTO:

A 
Pararenal fat
Renal Fascia
Perirenal fat
Renal Capsule
Kidney
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Look at slide 18 on YOUR PPT… this pic is on the exam with a second order question of what does this feature do!

A

hemisection of kidney with half of photo elements circled

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

Internal Anatomy of the Kidney:

A

Cortex

Medulla

Pyramid

Papilla

Columns

Lobe

Minor calyx

Major calyx

Renal Pelvis

Renal sinuses

Renal hilum

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

Internal Anatomy of the Kidney:

Contains all of the glomeruli and convoluted tubules of nephrons
Also makes the columns that lay between pyramids

A

Cortex-

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

Internal Anatomy of the Kidney:

Contains all of the loops of Henle and collecting ducts
Collection of all renal pyramids comprise the medulla

A

Medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Internal Anatomy of the Kidney:

one portion of the medulla
8-18 per kidney

A

Pyramid

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

Internal Anatomy of the Kidney:

narrow apex of the pyramid
Contains the papillary duct leading to minor calyx

A

Papilla

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

Internal Anatomy of the Kidney:

space between renal pyramids
Is a portion of the renal cortex

A

Columns-

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

Internal Anatomy of the Kidney:

  • a functional region within the kidney

Pyramid (medulla) + overlying cortex + ½ each adjacent column (cortex)

A

Lobe

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

Internal Anatomy of the Kidney:

  • small chambers that collect urine directly from papilla
    8-18 each kidney
A

Minor calyx

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

Internal Anatomy of the Kidney:

  • larger chambers that collect urine from multiple minor calyces
    2-3 each kidney, extensions of ureters
A

Major calyx

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

Internal Anatomy of the Kidney:

  • major calyces drain into one large chamber (pelvis),
    This mixes/collects all urine from entire kidney
    Connects to the ureter outside of the kidney
A

Renal pelvis

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

Internal Anatomy of the Kidney:

The kidney is 3-dimensional, so in between the other structures there are spaces that house some adipose tissue, the blood vessels, and nerve supply

A

Renal sinuses

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

Internal Anatomy of the Kidney:

  • a region
    Indentation of kidney where ureter emerges with blood and lymphatic vessels, and nerves
A

Renal hilum

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

Renal blood supply:

Renal blood flow is ____ per minute and ___ mL per kidney

Total amount of blood in adult is 4500-5500mL

Starts at ___ level and then branches from there into smaller vessels

Specialized capillary called a _____ is involved in this flow

A

1200mL; 600mL per kidney

aortic

glomerulus

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

This glomerulus allows for filtration, but not….

A

reabsorption

Exits out of glomerulus, no entrance back into it!

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

Talk through the blood supply of the kidney in order through the entire system…. (16 total)

A 
Aorta
Renal artery
Segmental artery
Interlobar artery
Arcuate artery
Interlobular artery (also called radial arteries)
Afferent arteriole
Glomerulus (modified capillary; tufted)
Efferent arteriole
Peritubular capillaries (both types of nephrons)
Vasa recta (juxtamedullary nephrons only)
Interlobular vein (also called radial veins)
Arcuate Vein
Interlobar Vein
Renal Vein
Inferior vena cavae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Blood flows into the kidney’s to get filtered

-It enters each corpuscle, gets filtered through the glomerulus, and exits the corpuscle to flow into a capillary system

—–Blood is filtered in the _____, where things can be removed only

—–When in the _____, blood will still act like it does in any other capillary in the body – stuff will move in and out of the capillaries depending on pressure

  • This capillary action acts as a….
  • —-Depending on the body’s needs, it can reabsorb/secrete more water/solutes as needed
A

glomerulus

peritubular capillaries/vasa recta

….secondary filter

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

Blood flows into the kidney’s to get filtered

As blood flows through, certain substances are removed from blood and placed into the urinary tubular system…. this is known as ?

A

This is known as filtrate

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

Filtrate is first found in the…..

From there is flows through the tubules and then into _____

While in these ducts, things can still be added to it, or removed from it

A

glomerular capsule (Bowman’s capsule)

collecting ducts

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

Once the filtrate leaves the collecting duct, it is then called _____

A

urine

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

Functional unit of the kidney –approximately 1,000,000 in each kidney

A

nephron

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

Nephron consists of two parts:

A

Renal Corpuscle

Renal Tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q
  • where blood is filtered (two parts)
A

Renal Corpuscle with two parts

1) Glomerulus
2) Glomerular capsule (aka Bowman’s capsule)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q
  • filtered contents (from blood; three parts)
A

Renal Tubule (three parts as follows):

Proximal Convoluted tubule (PCT)- attached to capsule

Loop of Henle (nephron loop)- middle section

Distal Convoluted tubule (DCT)- distant from capsule, empty into collecting duct

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

three parts of renal tubule (filtered contents)

A

PCT
LOH
DCT

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Corpuscle and both convoluted tubules reside in ____

A

cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Only Loop of Henle extends into the…

A

renal medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Two Different types of nephrons?

A

Cortical nephron

Juxtamedullary nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

– 85% of nephrons

  • —-Renal corpuscles lie in outer portion of renal cortex
  • —-Short loops of Henle (Just barely reach into outer region of medulla)
  • —-Peritubular capillaries only
A

Cortical nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

– 15% of nephrons

  • —-Renal corpuscles lie deep in the renal cortex
  • —-Long loops of Henle (Reach deep into medulla)
  • —-Peritubular capillaries that give rise to the Vasa recta (Vasa recta: capillary bed that extends into medulla surrounding the Loop of Henle)
A

Juxtamedullary nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

cortical nephrons have ___ capillaries only

A

peritubular capillaries only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

which nephron has short LOH?

A

Cortical nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

which nephron has long LOH?

A

Juxtamedullary nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

which nephron has Peritubular capillaries that give rise to the Vasa recta ?

A

Juxtamedullary nephron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

capillary bed that extends into medulla surrounding the Loop of Henle

A

Vasa recta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Cortical nephrons:

Short nephrons

_______ lie in the outermost portion of the cortex

Descending limb of loop of Henle barely dips into the ____

After a hairpin turn, the ascending limb of the Loop of Henle ____

A

Renal corpuscles

renal medulla

returns to the cortex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Cortical nephrons:

Peritubular capillaries

Arise from the _____

Intermingle throughout the ____

These then flow into _____ and eventually back into systemic circulation

A

efferent arteriole

proximal and convoluted tubules

interlobular veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Juxtamedullary Nephrons:

Long nephrons

—Renal corpuscles lie in the cortex

—Descending limb of loop of Henle dives deep into the ___ (which the longer descending loop means what?)

—After a hairpin turn, the ascending limb of the Loop of Henle climbs back to the cortex

A

renal medulla (Anatomy lends to very dilute and/or concentrated urine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Juxtamedullary Nephrons:

Peritubular capillaries

Arise from the efferent arteriole

Intermingle throughout the proximal and convoluted tubules

In the juxtamedullary nephrons only, a _____ exists coming off of these peritubular capillaries

A

specialized capillary system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Juxtamedullary Nephrons:

Vasa Recta

Coming from the peritubular capillaries, this type of capillary system dives deep into the renal medulla

Flows side by side each of the loops of Henle so that things can…..

A

….Flow out of the capillaries and into the filtrate as well as

Out of the filtrate and into the capillaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

The design with the use of vasa recta is extremely important for keeping a…

A

constant osmotic (pressure) gradient so that things can flow in and out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

short, wide afferent arteriole =

A

low-resistance input pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

efferent arteriole plus vasa recta =

A

high-resistance outflow pathway

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

flow is controlled by vasoconstriction of which arteriole?

A

afferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

The arteriole coming into the corpuscle/glomerulus

Brings blood in for filtration

Wider lumen, thicker walls

Has much more capability to constrict or dilate when compared to efferent arteriole

A

Afferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

This arteriole has much more capability to constrict or dilate when compared to the other…

A

afferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Ball of twine-like capillary structure that buds off of the afferent arteriole

A

Glomerulus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Glomerulus

Modified simple squamous epithelial cells called

A

podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Podocytes have fingerlike projections _____ that wrap around the glomerular capillaries

A

(pedicels)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

The arteriole leaving the corpuscle/glomerulus

A

Efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

Brings blood with larger solutes (i.e. proteins) into the peritubular capillaries (or vasa recta) and then back into systemic circulation

A

Efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Smaller lumen size, thinner walls

Smaller lumen size aids in back-pressure sometimes needed for glomerular filtration (continued later in lecture)

A

Efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

PCT/LOH/DCT/Collecting Duct

Together comprise?

A

Tubule System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

A single layer of epithelial cells forms the entire wall of the….

A

glomerular capsule, renal tubule, and ducts

Each section of cells has minor differences that allow for different functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

Simple cuboidal epithelial cells with prominent microvilli brush-border facing lumen (apical surface)

Microvilli increase surface area for absorption and secretion

A

PCT- proximal convoluted tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

(LOH) Loop of Henle (thin descending and thin ascending limb portions)

Histology?

A

Simple squamous epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

(LOH) Loop of Henle (thick ascending limb portion)

Histology?

A

Simple cuboidal to low columnar epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

DCT- distal convoluted tubule

Histology wise…
Most of DCT – ?
Last part of DCT- ?

A

Most of DCT – simple cuboidal epithelial cells

Last part of DCT- simple cuboidal epithelial cells that contain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

In the DCT…

  • receptors for ADH and aldosterone
A

Principal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

In the DCT…

  • help play a role in blood pH
A

Intercalated cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

Collecting Duct

Simple cuboidal epithelial cells that also contain:

A

Principal cells- receptors for ADH and aldosterone

Intercalated cells- help play a role in blood pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

Last part of DCT- simple cuboidal epithelial cells that contain:

A

Principal cells- receptors for ADH and aldosterone

Intercalated cells- help play a role in blood pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

The fluid that enters the afferent arteriole and into the glomerulus

The fluid that gets “filtered” in the glomerulus

A

Blood/Serum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

The leftover blood/serum and components not filtered into the glomerular capsule, leave the corpuscle via the

A

efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

The fluid/solutes that were filtered out of blood at the glomerulus

The fluid/solutes that enters the renal tubular system at the glomerular capsule

Fluid/solutes can still be reabsorbed/secreted over and over again

A

Filtrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

Once the filtrate leaves the collecting ducts, it is now called “urine”

A

Urine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

Nephrons and Collecting ducts perform three functions:

A

1) glomerular filatration
2) tubular reabsorption
3) tubular secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

water and many solutes found in blood move across the wall of the glomerulus, into the glomerular capsule (Bowman’s capsule) and into tubules

A

Glomerular filtration:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

water and solutes that are now flowing through the tubule system can get reabsorbed (~99% of filtrate is reabsorbed back into bloodstream)

A

Tubular reabsorption:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

due to the peritubular capillaries and vasa recta, there is still the chance to dump unwanted materials into the filtrate such as wastes, drugs, excess ions

A

Tubular secretion:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

once out of the collecting duct, there is no more opportunity for exchange; expelling waste matter

A

Excretion:

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

Garbage trucks dump smaller garbage (potential recyclables) into a mechanism that can sort out recyclables

A

Glomerular filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q 
Large items (such as appliances) are left on the truck to be taken elsewhere
Proteins/RBC’s that cannot make it through the filtration membrane
A

Still in blood, exits glomerulus via efferent arteriole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

Smaller refuse is placed onto a conveyor belt where workers separate the useful components (cans, plastic, glass)

A

Reabsorption of useful products (while in tubule system)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

The unusable refuse is thrown back into the garbage truck to be sent to the landfill

A

Wastes are secreted back into the ducts (filtrate) to be made into urine and excreted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

The amount that makes it into the glomerular capsule space and tubule system

A

Glomerular Filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

Adults create 150-180 liters of filtrate a day

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

99% is usually reabsorbed and returned to circulation

A

Glomerular Filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

Glomerular Filtration 99% reabsorbed…. Leaving only…

A

1-2 liters of urine produced a day

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

Filtration Membrane

Glomerular capillaries and podocytes form a “leaky” barrier in the capsule

A

Loosely packed- allows water and certain solutes to pass into capsular space

Prevents most plasma proteins, blood cells, platelets from getting into capsular space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

Filtration Membrane

Glomerular ___ and ____ form a “leaky” barrier in the capsule

A

capillaries and podocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

Filtration Membrane Consists of three layers of filtration:

A

Filtration Membrane Consists of three layers of filtration:

1) Fenestrations of endothelial cells (inner most layer of capillary)
- —Prevents blood cells from passing, but allows all other components of blood plasma through

2) Basement membrane/Basal lamina (middle layer of capillary)
- —Prevents large proteins from passing through
3) Slit membranes between pedicels (podocyte arms; outer most layer of capillary)
- —Prevents filtration of most other proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

Interspersed throughout the glomerular capillaries

Regulate surface area available for filtration

A

Mesangial Cells and Filtration Membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

Mesangial Cells and Filtration Membrane:

Regulate surface area available for filtration

When relaxed, _____

When contracted, _______

A

surface area is maximal

reduced area available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

when mesangial cells are relaxed surface area…

A

is maximal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

when mesangial cells are contracted surface area…

A

reduced area available

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

Glomerular Filtration Pressure

Although still capillaries, pressure is higher in these than in any other capillaries in the body

A

Larger surface area

Larger fenestrations for easier filtration

Efferent arteriole is smaller than the afferent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

Efferent arteriole is smaller than the afferent

This then requires more pressure to get plasma…

This pressure builds backwards into the glomerulus…

A

…OUT of the glomerulus through the efferent arteriole

…increasing filter pressure (positive pressure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

Pressure in glomerulus pushing outward into capsular space

Usually 55mmHg

A

Glomerular blood hydrostatic pressure (GBHP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

Hydrostatic pressure exerted by the fluid in capsular space that pushes inward on the visceral glomerular membrane

“back pressure”

Usually 15mmHg

A

Capsular hydrostatic pressure (CHP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

Pressure due to proteins in blood plasma (mainly albumin)

Opposes filtration (Pulls on fluid/solutes to keep them in the glomerulus if possible)

Usually 30mmHg

A

Blood colloid osmotic pressure (BCOP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

Net Filtration Pressure / NFP is the pressure that is supposed to

A

PROMOTE filtration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

NFP = ?

in healthy kidneys about how many mmHg?

A

NFP= GBHP-CHP-BCOP
NFP= 55mmHg-15mmHg-30mmHg
10mmHg – normal NFP in healthy kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

As long as the NFP is a positive number,

A

filtration will occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

If NFP calculates into a negative number,

A

NO FILTRATION is occurring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

Promoting filtration eventually leads to

A

urine production

123
Q

the amount of blood filtered by the kidneys’ glomeruli into capsular space per unit time

124
Q

average adult GFR

A

125mL/min in average adult

125
Q

Homeostasis of body fluids requires a _____ GFR

A

near constant

126
Q

If GFR too fast-

A

filtrate may pass too quickly and required substances may not be reabsorbed

127
Q

If GFR too slow-

A

nearly all filtrate may be reabsorbed and certain wastes may not be excreted efficiently

128
Q

CALCULATING GFR

An “estimated” rate only as it involves calculations and not actual measurements

A 
Calculated using the serum creatinine levels and some or all of the following:
Age
Race
Weight 
Gender
129
Q
  • waste from the breakdown of muscle (normal)
A

Creatinine

130
Q

As blood is filtered through the nephrons, the kidney neither reabsorbs or metabolizes this substance

A

Creatinine

131
Q

Should freely pass through the filtration membrane and be urinated out

A

Creatinine

132
Q

In a normal healthy adult, the serum level should be near or at the same level of the urine creatinine clearance (24hour urine collection)

IF URINE LEVEL LOW?
CAUSING INCREASED SERUM OF WHAT?

A

If the urine level is low, this means the kidneys are not filtering the serum creatinine properly (kidney damage)

Usually means that the serum level will be elevated

133
Q

In calculating the estimated GFR, many studies found that the African American population (especially Afro-Caribbean Black patients) had a much higher serum creatinine (SCr) level

A

Generally have increased muscle mass

Generally have higher rates of muscle breakdown

134
Q

When accounting for this shift of normal levels, it shows that the average African American patient will have a “higher normal” GFR

A

21% above the normal levels for non-black patients

135
Q

GFR directly related to pressures that determine net filtration pressure

A

Ex: Severe blood loss reduces mean arterial pressure as well as glomerular blood hydrostatic pressure

If GBHP drops by even 10mmHg, filtration in the glomerulus stops (remember the NFP is what is needed to force filtration)

136
Q

If GBHP drops by even 10mmHg, filtration in the glomerulus….

A

….stops (remember the NFP is what is needed to force filtration)

137
Q

Mechanisms that regulate GFR?

A

1) Renal autoregulation
- –Innate actions that occur within the kidney

2) Neural regulation
- –Sympathetic nervous system input (or reduction of input)

3) Hormonal regulation
- –Angiotensin II
- –Atrial natriuretic peptide (ANP)

138
Q

Mechanisms that regulate GFR

Renal autoregulation?

A

Innate actions that occur within the kidney

139
Q

Mechanisms that regulate GFR

Neural regulation?

A

Sympathetic nervous system input (or reduction of input)

140
Q

Mechanisms that regulate GFR

Hormonal regulation?

A

Angiotensin II

Atrial natriuretic peptide (ANP)

141
Q

GFR- Renal Autoregulation

Kidney’s help maintain their own GFR by two mechanisms:

A
  1. Myogenic mechanism

2. Tubuloglomerular feedback

142
Q

Myogenic Mechanism

immediate increase in BP causes?
which can cause?

A

Immediate increase in BP

causes

Myogenic vasoconstriction

which can cause

Compensatory vasodilation

143
Q

increased BP (as in exercise) causes stretching of afferent arteriole, this causes smooth muscle contraction of afferent arteriole, reduces renal blood flow, which reduces GFR

A

Myogenic mechanism-

144
Q

This helps to preserve nephron integrity with increased blood pressure

When threat of increased BP is reduced, afferent arteriole may vasodilate to increase GFR to balance out the system

A

Myogenic mechanism-

145
Q

the Juxtaglomerular apparatus (JGA; see following slides for full explanation)

A

Tubuloglomerular feedback

146
Q

When GFR increases, rate through the tubules increase

Reabsorption of Na+, Cl- and water reduce due to rate of flow

Macula densa cells sense the increased levels of these in filtrate

These levels inhibit the release of nitric oxide (NO; vasodilator)

If NO inhibited, afferent arterioles constrict, lowers GFR

Lowered GFR slows rate through tubules

A

Tubuloglomerular feedback-the Juxtaglomerular apparatus (JGA)

147
Q

Tubuloglomerular feedback-the Juxtaglomerular apparatus (JGA)

A

When GFR increases, rate through the tubules increase

Reabsorption of Na+, Cl- and water reduce due to rate of flow

Macula densa cells sense the increased levels of these in filtrate

These levels inhibit the release of nitric oxide (NO; vasodilator)

If NO inhibited, afferent arterioles constrict, lowers GFR

Lowered GFR slows rate through tubules

148
Q

A complex structure that has the ability to affect systemic blood pressure through the autoregulation of tubuloglomerular feedback

A

Juxtaglomerular Apparatus (JGA)

149
Q

There is one JGA for every _____

150
Q

Juxtaglomerular Apparatus (JGA) contains….

A

Juxtaglomerular cells
—Found in the walls of the afferent arteriole

Macula densa cells
—Found in the walls of the distal convoluted tubule

Lacis cells (modified mesangial cells)
---Located between afferent arteriole, efferent arteriole, and DCT
151
Q

—Found in the walls of the afferent arteriole

efferent arteriole, and DCT

A

Juxtaglomerular Apparatus (JGA) Cells including…

Juxtaglomerular cells (AA)

Macula Densa Cells (DCT)

Lacis Cells (Modified Mesangial Cells / Extraglomerular)

152
Q

—Found in the walls of the distal convoluted tubule

A

Macula densa cells

153
Q

—Located between afferent arteriole, efferent arteriole, and DCT

A

Lacis cells (modified mesangial cells) AKA extraglomerular mesangial cells

154
Q

The afferent arterioles contain

A

juxtaglomerular cells

155
Q

Modified smooth muscle cells that have two functions:

A
  1. Detect when blood pressure is too low (by sensing the lack of stretch of the afferent arteriole wall)
  2. They synthesize, store, then secrete hormone/enzyme Renin (described later in RAAS)
    - —-Renin causes a cascade of events that helps to increase blood pressure when needed
156
Q

The distal convoluted tubule (where it meets the afferent arteriole) contains

A

macula densa cells

157
Q

macula densa cells

Closely packed specialized cells that have two functions

A
  1. Detect increase in NaCl (Sodium Chloride) concentrations in the filtrate
  2. In response to this concentration check, these cells release
    ATP, Adenosine in various concentrations which act locally
    —-These trigger contraction of afferent arteriole
    —-This causes GFR to reduce, which reduces the rate tubule flow
158
Q

In response to this concentration check, these cells release ATP and Adenosine in various concentrations which act locally to do these two things…

A

macula densa cells which…

  • —These trigger contraction of afferent arteriole
  • —This causes GFR to reduce, which reduces the rate tubule flow
159
Q

located in between the afferent, efferent and distal convoluted tubule junction

A

Lacis Cells (Modified Mesangial cells)

160
Q

Contract or relax to make small regulatory changes in response to the signals that the other JGA cells are sending

A

Lacis Cells (Modified Mesangial cells)

161
Q

Together the macula densa, juxtaglomerular cells, and Lacis cells make the

A

Juxtaglomerular Apparatus

162
Q

tubuloglomerular feedback

A

Depending on the filtrate analysis at this location, the filtration performance of the glomerulus can be changed

Helps regulate blood pressure within the kidneys
—–This can eventually effect systemic blood pressure

163
Q

Blood vessels of the kidney are supplied by

A

sympathetic nervous system fibers only

164
Q

At rest, sympathetic stimulation is low:

Afferent and efferent arterioles are ___

Blood flow into and out of the glomerulus is _____

A

Afferent and efferent arterioles are dilated

Blood flow into and out of the glomerulus is relatively equal

165
Q

With greater sympathetic stimulation (exercise, fight/flight)

_____ of the afferent arteriole occurs

Blood flow ____ into glomerulus

GFR __________

A

Vasoconstriction of the afferent arteriole occurs

Blood flow decreases into glomerulus

GFR decreases

166
Q

This decreases because during sympathetic stimulation we need blood elsewhere in the body…

This also protects the nephrons from the rapid rise in blood pressure

A

GFR decreases

167
Q

two hormones that control regulation of GFR?

A

Angiotensin II- reduces GFR

  • –Very potent vasoconstrictor
  • –Mostly acts on efferent arterioles
  • –Reduces renal blood flow

Atrial natriuretic peptide (ANP)- increases GFR

  • –Secreted by the atria (heart)
  • –Usually secreted in response to increase in volume
  • –Markedly vasodilates afferent and efferent arterioles
  • –GFR increases
168
Q

Passive movement occurs when pressure gradients allow flow of something from a high concentration to a low concentration; it does not require ATP energy to occur
Example in kidneys?

A

Example: Glomerular filtration occurs from pressures alone, not from ATP expenditure

169
Q

Active movement occurs usually against the concentration gradient and with the help of ATP expenditure

Ex in kidneys?

A

Example: Sodium/Potassium pumps (Na+/K+) expend energy converting ATP to ADP

170
Q

Tubular Reabsorption

Normally 99% of filtrate is reabsorbed

Epithelial cells all along the renal tubule and ducts reabsorb, but the ____ cells make the largest contribution to reabsorption

Solutes that are both actively and passively reabsorbed include….

A

PCT

Glucose, amino acids, urea, sodium, potassium, calcium, chloride, magnesium, bicarbonate, and phosphates

171
Q

Solutes that are both actively and passively reabsorbed include….

A 
Glucose, 
amino acids, 
urea, sodium, 
potassium, 
calcium, 
chloride, 
magnesium, 
bicarbonate, and 
phosphates
172
Q

Once fluid passes through the PCT, cells located more distally “fine tune” the reabsorption process…. where does this occur?

A

Loop of Henle, DCT, Collecting duct

173
Q

If small proteins and peptides are passed through the glomerular filter….

A

They are usually reabsorbed by pinocytosis

174
Q

Reabsorption can occur by

A

Paracellular reabsorption

Transcellular reabsorption

175
Q

Reabsorption between adjacent tubule cells

Passive movement only
Thought to account for up to 50% of reabsorption

A

Paracellular reabsorption

176
Q

Reabsorption - through the tubule cell itself

Passive and Active movement

A

Transcellular reabsorption

177
Q
  • the lumen side of the cell
A

Apical membrane

178
Q
  • the interstitial side of the cell
A

Basolateral membrane

179
Q

look at image of transcellular vs paracellular reabsorption from the slides

A

good job hero

180
Q

Water follows solutes almost always and

Solute reabsorption drives water reabsorption via ____

This is called ____

A

osmosis

obligatory water reabsorption

181
Q

obligatory water reabsorption

90% of actual water reabsorption by the kidneys occurs with the reabsorption of

A

Sodium (Na+)
Chloride (Cl-)
Glucose

182
Q

Obligatory Water Reabsorption occurs in

A

the PCT and the descending limb of the loop of Henle

183
Q

These segments are always permeable to water

A

the PCT and the descending limb of the loop of Henle

184
Q

After obligatory water reabsorption…. Reabsorption of the remaining 10% of water occurs by?

A

facultative water reabsorption

185
Q

Regulated by ADH

Occurs in the late DCT and collecting ducts

A

facultative water reabsorption

186
Q

facultative water reabsorption occurs in the ?

A

late DCT and collecting ducts

187
Q

The transfer of materials from the capillaries (peritubular and/or vasa recta), interstitial spaces and tubule cells into the filtrate

A

Tubular Secretion

188
Q

Tubular Secretion

Secreted substances include (but not limited to)

A

Hydrogen ions
—-Secretion of hydrogen ions helps to control the blood pH

Potassium

Ammonium ions

Creatinine

Certain drugs like penicillin

189
Q

Remember…the general idea is to make the concentration and the net-charge of solutes and water the same

A

This never actually occurs though because

There is a constant turnover of new blood coming into the kidney’s

The body signals the need for certain elements to be reabsorbed or secreted based on an attempt for homeostasis

190
Q

there is constant movement of things across these membranes (tubule cell : interstitial fluid : capillary)…this constant movement generates

A

This constant movement generates an osmotic gradient as well as an electric gradient (+/-)

191
Q

___ is a nitrogenous waste created when proteins are catabolized (broken down)

192
Q

This is a very toxic substance and if left to accumulate in this form, it would be deadly

193
Q

Much of the ammonia made in the body is circulated to the ____ (where it is converted to urea) or is excreted in urine

194
Q

is much less toxic than ammonia, but can still be deadly if left to accumulate

195
Q

Urea plays a significant role in creating and maintaining the

A

osmotic gradient in the renal medulla

196
Q

This “safeguards” the body’s supply of an important buffer

A

Most of the bicarb (HCO3-) is reabsorbed in the PCT

197
Q

where is bicarb reabsorbed

198
Q

Bicarb cannot be reabsorbed in complete form, has to be “processed” to be reabsorbed

A

When H+ is secreted into lumen of the tubule in the PCT, the HCO3- reacts with it to form H2CO3 (carbonic acid)

This then dissociates into CO2 and H2O
CO2 diffuses into the tubule cells and joins with H2O already in the cell to form H2CO3

This H2CO3 then dissociates into H+ and HCO3-

199
Q

For every H+ secreted into tubular lumen, _______ are reabsorbed

A

one HCO3- and one Na+

200
Q

Largest amount of solute and water reabsorption from filtered fluid occurs in the

A

Proximal Convoluted Tubule - PCT

201
Q

100% of glucose, amino acids, vitamins

and 90% of bicarb are reabsorped here

202
Q

Sodium (Na+) is actively transported out of tubule and into interstitial fluid…. what is co-transported?

A

Glucose and amino acids are co-transported with Na+

203
Q

As Na+ moves into blood, this creates a significantly positive environment in blood causing….

A

Chloride (Cl-) ions passively move from filtrate into interstitial fluid to help balance this

204
Q

Here Urea passively moves out of tubule

205
Q

Bicarb is reabsorbed here

206
Q

Movement of ______ into interstitium creates a significant osmotic imbalance now, so water is obligated to move out of filtrate and into interstitum by osmosis

A

Na+ and Cl-

207
Q

Cells lining the PCT and the descending LOH are especially permeable to water because of the presence of

A

aquaporin-1 channels

208
Q

These are protein water channels that increase the rate of water movement

A

aquaporin-1 channels

209
Q

The osmosis of water will often bring K+ and Ca++ with it in a motion called

A

solvent drag

210
Q

solvent drag

A

The osmosis of water will often bring K+ and Ca++

211
Q

Multiple functions of PTH

A

PTH stimulates cells in the PCT to secrete phosphate

PTH stimulates calcitriol (Vitamin D) to be made in PCT cells and then be absorbed into blood
—-Calcitriol circulates to intestines where it causes more calcium from digestive system to be absorbed

PTH also stimulates cells in the DCT to reabsorb more calcium

212
Q

PTH stimulates cells in the PCT to secrete

213
Q

PTH stimulates calcitriol (Vitamin D) to be made in…

A

PCT cells and then be absorbed into blood

214
Q

PTH also stimulates cells in the ____ to reabsorb more calcium

215
Q

In the entire LOH, unlike the PCT, solute and water reabsorption are

A

independently regulated

216
Q

15% of water left

A

(in descending portion only, none in the ascending portion)

217
Q

mostly water reabsorption and solute secretion (concentrates the filtrate)

A

Descending limb

218
Q

no water reabsorption, but reabsorption of solutes occurs (dilutes the filtrate)

A

Ascending limb

219
Q

This region is passively permeable to water and solutes

A

Descending Limb LoH

220
Q

Solute reabsorption occurring simultaneously in the _____ creates a higher concentration (osmolarity) in the interstitial fluid

A

ascending limb

221
Q

Descending Limb LoH

increased interstitial fluid osmolarity (from ascending limb) forces the descending limb to attempt to find equilibrium causing….

A

Causes water reabsorption and solute secretion to occur in the descending limb

Urea, Na+, and Cl- are secreted into tubule

222
Q

Descending Limb LoH

More solutes and less water causes the “first” concentration of filtrate inside the tubule (hyperosmotic)

A

Descending Limb LoH

223
Q

Ascending Limb LoH

This region is passively permeable to small solutes, but impermeable to water (no water reabsorption occurs here)

A

Thin portion

224
Q

Active reabsorption (movement out of tubule) of Na+, K+, Cl- occurs here, but this region is still impermeable to water

A

Thick portion

225
Q

This means that as filtrate moves up the ascending limb, it dilutes even more

A

Active reabsorption (movement out of tubule) of Na+, K+, Cl- occurs here, but this region is still impermeable to water

226
Q

Early portion of the DCT

very little Na and Cl are left and only 10-15% of water… but at the late portion of DCT

A

By the time filtrate reaches this portion, 90-95% of filtered solutes/water have been reabsorbed and returned to interstitium/bloodstream

227
Q

Specialized cells found intermixed in the DCT and throughout the collecting ducts

A

Principal cells

Intercalated cells

228
Q

In the DCT and collecting ducts, the amount of reabsorption of solutes/water is dependent on feedback from the body in general

A

Hormonal (ADH, Aldosterone, Atrial Natriuretic Peptide)

Osmoreceptors throughout the body (ex: body requires more sodium than what’s already been reabsorbed)

229
Q

DCT is similar to PCT in that Na+ reabsorption occurs via

A

active transport

230
Q

In DCT/Collecting ducts though, the cells are relatively still impermeable to water, so…

BUT… when the need arises, there is a mechanism that gets activated in these cells that allows them to be able to ____

A

…water does not follow Na+ via osmosis

selectively reabsorb water

231
Q

______ causes principal cells in the DCT and collecting ducts to become permeable to water

A

Anti-Diuretic Hormone (ADH)

232
Q

ADH targets ____ in the DCT and collecting ducts

A

principal cells

233
Q

Antidiuretic Hormone (ADH)

Triggers these cells to generate ____ in the apical membrane of the cells lining the tubule

A

aquaporin-2 channels

The presence of these TEMPORARY channels allows the tubule wall to become more permeable to water via osmosis

234
Q

Antidiuretic Hormone (ADH)

The more ADH that is present, the more

A

aquaporin-2 channels will be generated

235
Q

Antidiuretic Hormone (ADH)

In general, in the presence of ADH, we produce a small quantity of….

A

highly concentrated urine

236
Q

ADH triggers aquaporin 2 channels in the….

A

apical membrane of the cells lining the tubule

237
Q

Incidentally, in the presence of ADH, when more water is reabsorbed, it creates an osmotic imbalance when it gets to the…

A

distal collecting duct

238
Q

osmotic imbalance from ADH forces ___ to be reabsorbed

239
Q

The addition of urea in the interstitial fluid from the collecting duct assists in increasing the high osmolarity in the interstitial fluid

A

This helps to keep the osmotic gradient constantly moving

The urea that is reabsorbed at the distal collecting ducts migrates through interstitial fluid and gets secreted in the descending limb of the loop of Henle (Urea recycling)

240
Q

When ADH is at it maximal secretion

A

Body can produce as little as 400-500mL of very concentrated urine each day

The rest is returned to the interstitium/blood stream instead of being urinated out

241
Q

When blood pressure/volume stabilizes

A

ADH levels decline causing

The aquaporin-2 molecules to be removed from principal cells

Normal volume of normal to dilute urine produced

242
Q

Aquaporin-2 molecules are only effective in the presence of ADH whereas aquaporin-1 molecules are….

A

…independently functioning in the PCT/LOH

243
Q

Under the influence of aldosterone, principal cells cause the following:

A

Sodium reabsorption (usually brings water with it)

Potassium secretion

244
Q

What causes aldosterone to be released?

A

Hyperkalemia

Presence of angiotensin II
—This occurs when the renin-angiotensin-aldosterone system is stimulated by low blood volume or pressure

245
Q

The principal cells are responsible for…

A

secretion of K+ and reabsorption of Na+

246
Q

Look at Principal cells graphic!

247
Q

intercalated cells are stimulated by

A

various osmoreceptor readings in reference to pH and potassium levels

248
Q

intercalated cells are stimulated by

A

various osmoreceptor readings in reference to pH and potassium levels

249
Q

Causes secretion of hydrogen (H+) ions
Causes reabsorption of bicarb
Causes reabsorption of potassium (K+)

A

Type A Intercalated Cells

250
Q

Causes reabsorption of hydrogen (H+) ions
Causes secretion of bicarb
Causes secretion of potassium (K+)

A

Type B Intercalated Cells

251
Q

When ANP is stimulated, it has direct actions on the cells located in the

A

DCT and the Collecting Ducts

252
Q

Inhibits the reabsorption of sodium and water

Also inhibits the renin-angiotensin-aldosterone system

A

Atrial Natriuretic Peptide

253
Q

Activated in response to low renal vascular flow/pressure

A

Renin-Angiotensin-Aldosterone System

254
Q

System activated when blood volume/pressure is too low, no longer stretching the walls of the afferent arteriole

A

Renin-Angiotensin-Aldosterone System

255
Q

This causes the _______ to secrete the hormone/enzyme renin into the blood stream

At the same time, angiotensinogen is released by hepatocytes into the blood

A

juxtaglomerular cells

256
Q

secrete renin

A

juxtaglomerular cells

257
Q

Renin finds angiotensinogen and cleaves off a 10-amino acid peptide

A

This converts angiotensinogen to angiotensin-1

258
Q

is the active form of the hormone

A

Angiotensin II

259
Q

Angiotensin I continues to course through the blood until it reaches the lungs
Here, angiotensin-I is converted to angiotensin-II by

A

lung endothelial angiotensin converting enzyme (ACE)

260
Q

Angiotensin II affects renal physiology in three ways:

A

Decreases GFR by causing vasoconstriction of afferent arteriole

Enhances Na+, Cl- and water reabsorption in the PCT

Stimulates the adrenal cortex to release aldosterone

261
Q

Aldosterone stimulates the principal cells in the collecting ducts to reabsorb more ___ and secrete more ____

A

Na+ and Cl- and secrete more K+

262
Q

With increased reabsorption of Na+ and Cl-, more water is reabsorbed which causes INCREASED blood volume and blood pressure

A

duh… thanks raas

263
Q

Body fluid volume homeostasis largely dependent on rate of water excretion in urine

A

When water intake is high, kidneys produce large amount of dilute urine

When water intake is low, kidneys produce a small amount of concentrated urine

264
Q

The regulation of plasma osmolarity and volume are the responsibility of….

A

the Loop of Henle, the DCT, and the collecting ducts

265
Q 
Concentrating urine (initially)
----Permeable to water mostly, therefore concentrating the filtrate
A

Descending limb of LOH

266
Q 
Diluting urine (initially)
----Impermeable to water, therefore diluting the filtrate
A

Thick ascending limb of LOH

267
Q

Where final dilution/concentration occurs

Where the majority of ADH has its action

A

DCT + Collecting Ducts

268
Q

In absence of ADH

A

Urine is diluted

269
Q

In presence of ADH

A

Urine is concentrated

270
Q

Dilution/Concentration in the DCT and the collecting ducts is controlled by the presence or absence of

271
Q

Dilution/Concentration in the ___ and ___ is controlled by the presence or absence of ADH

A

DCT and the collecting ducts

272
Q

Urinalysis metrics:

A

Volume- 1-2 liters in 24 hour period (24 hr urine collection)
Color- yellow or amber, varies with urine concentration and diet (beets, medications [pyridium], kidney stones can cause blood in urine)
Turbidity- transparent when voided, becomes cloudy with time
Odor- mildly aromatic, becomes ammonia-like with time
Bacteria turning urea back into ammonia
pH- ranges from 4.6-8.0, average is 6.0, varies with diet, high protein increases acidity, vegetarian increases alkalinity
Specific gravity- density (ratio of weight of solutes vs water) usually 1.001-1.035 (the higher the solutes the higher the value)

273
Q

normal urine is protein free

274
Q

Urea (from breakdown of proteins)

Creatinine (from breakdown of creatine phosphate in muscle)

Uric Acid (breakdown of nucleic acids)

Urobilinogen (breakdown of hemoglobin)

Small amount of fatty acids, pigments, enzymes, and hormones

A

Water accounts for 95% of urine

275
Q

Two blood tests can provide kidney function information

A

Blood Urea Nitrogen (BUN)- measures urea (uremia)

Plasma creatinine- catabolism of creatine phosphate in skeletal muscle

276
Q

This urea results from the catabolism and deamination of amino acids (proteins) in the liver

Urea can be reabsorbed from filtrate to help create/maintain an osmotic gradient in the kidneys

When GFR reduces severely (as in renal disease), BUN increases

A normal BUN level is 7-20mg/dL

A

Blood Urea Nitrogen (BUN)- measures urea (uremia)

277
Q

Normally remains steady as the rate of creatinine excretion in urine equals its discharge from muscle
There is NO use for creatinine in the body, so we should excrete much, if not all of it in the urine
A normal SERUM creatinine level is anything below 1.6mg/dL

A

Plasma creatinine- catabolism of creatine phosphate in skeletal muscle

278
Q

The volume of plasma (mL) that can be completely cleared of a substance per unit time (min)

For example the clearance of glucose is normally zero because normally 100% of glucose is reabsorbed, nothing gets excreted

A

If a drug is being administered (like penicillin) that has a high clearance (excreted in high doses in the urine) then the dosing of the medication must be high to be effective

279
Q

plant polysaccharide, easily passes through the filter and is excreted in urine 100%

A

Inulin

Great measure of true GFR

280
Q

Inulin is administered by IV continuously while concentration of plasma and urine inulin are measured along with urine flow rate

A

Great method but inulin is not produced in the body so this test is difficult to do

281
Q

As creatinine is filtered, not reabsorbed, its clearance is a good estimate of GFR

A

At times, can overestimate GFR by 10-20%

Lab values needed: 24 hr urine volume (convert mL/day to mL/min), plasma and urinary concentration of creatinine (convert to mg/mL)

282
Q

Urine Transportation, Storage, and Elimination route….

A

Collecting ducts –-papilla - papillary ducts - minor calyces – major calyces – renal pelvis – ureters – urinary bladder – urethra – toilet

283
Q

Urine transport by peristalsis (renal pelvis to urinary bladder) aided by

A

hydrostatic pressure and gravity

284
Q

Ureter - Pass obliquely into _____ aspect of bladder

A

posterior/inferior

285
Q

Ureter Anatomy

Although no valve is present, a physiologic valve exists

A

When the bladder fills with urine, it pulls the bladder down which closes these valves so no “backflow” occurs

Called the anti-reflux mechanism

286
Q

anti-reflux mechanism

A

When the bladder fills with urine, it pulls the bladder down which closes these valves so no “backflow” occurs

287
Q

External urethral sphincter

A

Skeletal muscle (composed of deep perineal muscles/pelvic floor)

Voluntary

Sits just below the prostate (in males)

Is at the opening of the external urethral orifice (in females)

288
Q

Prostatic
Membranous
Spongy

A

Male Urethra

289
Q

circular smooth muscle forms internal urethral sphincter

A

Prostatic:

290
Q

Contains:

Duct that transports prostatic fluids
Duct that transports sperm

A

Prostatic urethra

291
Q

shortest region passing through urogenital diaphragm, circular skeletal muscle forms external urethral sphincter

A

Membranous urethra (Intermiediate)

292
Q

longest region passing through penis

A

Spongy urethra

293
Q

Spongy Urethra contains openings of

A

Bulbourethral (Cowper’s gland)-delivers alkaline fluid to help neutralize acidity of urethra

294
Q

Female urethra is _____ to pubic symphysis, runs inferior/anterior from the _____ to the ____

A

Posterior

bladder neck and to the vaginal vestibule

295
Q

located between clitoris and vaginal orifice

A

Female Urethra

296
Q

female urethra think

A

musocas

muscularis

297
Q

consists of epithelium and lamina propria of female urethra

A

Mucosa of female urethra

298
Q

Transitional epithelium near bladder; middle section is stratified or pseudostratified columnar; near external urethral orifice is nonkeratinized, stratified squamous

A

Mucosa of female urethra

299
Q

circular, smooth muscle of female urethra

A

Muscularis:

300
Q

Parasympathetic reflex initiates the mechanism for urination (micturition) which causes

Involuntary contractions of the detrusor muscle

Internal urethral sphincter to open

This causes urine to move from the bladder into the urethra

This causes the sensation that we perceive as our body telling us we need to urinate soon

A

Micturition

301
Q

Micturition causes Involuntary contractions of the

A

detrusor muscle

302
Q

After micturition…. Then, voluntary contraction of the external urethral sphincter helps to prevent urination until the appropriate time

A

Voluntary relaxation of this sphincter allows the flow of urine to occur

303
Q

What are the two types of mesangial cells?

A

Intraglomerular vs Extraglomerular

Intraglomerular Mesangial Cells are inbetween the glomerulus in the Bowmans capsule

Extraglomerular cells are also known as modified mesangial cells AKA Lacis Cells and are located between the AA, EA, and DCT

AP II (7 decks)

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