EXAM 2- Kidneys Flashcards
(104 cards)
1
Q
What are the 2 major active membrane transport processes
A
Active and Vesticular transport
2
Q
Why does both VT and AT require ATP to move solutes across a plasma membrane
A
Solute too large for channels, Solute is not lipid soluble, or solute os not able to move down a concentration gradient
3
Q
What are the three types of diffusion
A
Simple, facilitated, osmosis
4
Q
How much ATP is used in the kidney daily
A
30-35%
5
Q
What does it mean when blood osmolarity decreases
A
you have too much water (Overhydrated), you pee more to save salts
6
Q
What does it mean when blood osmolarity increases
A
you have not enough water (dehydrated), you pee less H2O to rid salts
7
Q
What is an antiporter
A
transport 1 substance into cell while transporting a different substance out of the cell while transporting a different substance out of the cell
8
Q
What is are symporters
A
transport 2 different substances in the same direction
9
Q
What is primary AT
A
required energy comes directly from ATP hydrolysis, which causes a shape change of transport protein
10
Q
What is secondary AT
A
Required energy is obtained indirectly from ionic gradients created by primary active transport
11
Q
What are leakage channels
A
Located in the membrane, results in leaking of Na+ into the cell and K+ out of cells
12
Q
Are sodium-pot pumps antiporters or symporters
A
Antiporter, Na out of cell and K into cells, against their respective gradients
13
Q
Why are there leakage channels
A
Because the membrane is selectively permeable, so the Na and K leak back in/out
14
Q
What is the ratio of Sodium and Potassium
A
3:2
15
Q
Vesticular transport
A
Involves transport of large particles, marcomolecules and fluids across the membrane in membranous sacs (vesicles)
16
Q
Does vesticular transport require ATP
A
Yes! cellular energy, typically ATP
17
Q
What does the vesticular transport process include
A
Endocytosis, Exocytosis, Transcytosis
18
Q
Endocytosis
A
- Transport into cell (cytoplasm)
- Involves formation of protein coated vesicles
- Involves receptors
- When the vesicle is pulled into cell it can fuse with lysosome or undergo transcytosis
- Some pathogens can hijack receptors for transport into cell
19
Q
What are the three types of endocytosis
A
Phagocytosis, Pinocytosis, Receptor mediated endocytosis
20
Q
Exocytosis
A
transports out of cell (cytoplasm)
- Process where material is ejected from cell
- Ejected material en enclosed in secretory vesicle
21
Q
Transcytosis
A
Transport into, across and out of cell (Cell highway)
22
Q
What is phagocytosis
A
The cell engulfs a large particle by forming a projected psudeopod around it. Encloses it within a phagosome.
- Phagosome combines with a lysosome and digests contents
23
Q
In phagocytosis what are the vesicle receptors capable of binding too?
A
Microorganisms or solid particles
24
Q
What is Pinocytosis
A
- Cells gulp a drop of extracellular fluid containing solutes into tiny vesicles.
- No receptors are used, non-specific process
- Main way for nutrient absorption in small intestine
- Membrane components are recycled into membrane
25
What type of endocytosis is referred to as cell drinking or fluid phase endocytosis
Pinocytosis!
26
What is Receptor mediated endocytosis?
- Involves endocytosis and transcytosis of specific molecules
- Many cells have receptors embedded in clathrin-coated pits. To be internalized along with specific molecules bound
27
In Receptor mediated endocytosis what do extracellular substances bind to?
Specific Receptor proteins, that enable the cell to ingest and concentrate specific substances in protein coated vesicles. The substances can be released inside the cell or digested in a lysosome
28
What activates exocytosis
Cell surface signals or changes in membrane voltage
29
What are the proteins on vesicles for exocytosis
V-SNARE finds and hooks to target T-SNARE proteins on membrane
30
What trigers endocytosis
Docking process (V/T-SNARES)
31
What are examples of substances to be exocytosed?
Hormones, neurotransmitters, mucus, cell wastes
32
What is the process of exocytosis
1. Membrane bound vesicles migrates to plasma membrane
2. There, Proteins at the vesicle surface (V-SNARES) bind with T-SNARES
3. Vesicle and plasma membrane fuse and a pore opens up
4. Vesicle contents are released to cell exterior
33
What is the process of Docking
When the Vesicle and plasma membrane fuse and a pore opens up
34
What is true urine
urine that is fully formed
35
Where does formative urine go to become urine
leave the kidneys
36
Why would you take a diuretic drug?
With high BP, to pee more because you have excess blood volume you need to rid. The Diuretic drug reduces BV which reduces BP
37
What is an Anti-diuretic?
Drug that makes you conserve water, pee less. For when you are dehydrated
38
What is creatine
byproduct of muscle contraction
39
What creates a hyperotnic solution
Too much urea
40
Renal control of electrolyte balance
Sodium, Magnesium, Zinc, Iron
41
Renal control of Acid-Base Balance
too many protons, kidneys flush them out
42
Urinary System Organs
Urinary Bladder, Paired Ureters, and urethra
43
Urinary Bladder
Provides a temporary storage reservoir for urine
44
Paired Ureters
transport urine from kidneys to bladder
45
Urethra
transports urine from bladder out of body
46
How many gallons of blood is filtered daily
180 Liters (45 gallons)
47
What are the functions of the Kidneys
- Filter blood, allows toxins, metabolic wastes and excess ions to leave body in urine
- Regulate volume and chemical makeup of blood
- Maintain proper balance of water/salts and acids/bases
48
What are the mechanisms of Urine Formation
- Glomerular Filtration
- Tubular Absorption
- Secretion
49
Filtration Membrane
- Entry points of bowman's capsule has filtration slits
- Fenestrations don't allow blood through, only h2o and glucose and cells
50
What are fenestrated Capillaries
- Found where active capilary absorption or filtrate formation occurs (small intest., endocrine glands, kidneys)
51
What are fenestrated Capillaries characterized by
- An endothelium riddled with pores
- Greater permeability to solutes and fluids then other capillaries
52
Golmerular Filtration
- Principles of fluid dynamics that account for tissue fluid in all capillary beds apply to the glomerulus as well
53
Why are glomerulus beds more efficient than other capillary beds?
- Filtration membrane is significantly more permeable
- Glomerulus BP is higher
- Has higher Net Filtration Pressure
- Plasma proteins are not filtered, and used to maintain osmotic pressure of blood
54
What is blood filtered by
Hydrostatic pressure
55
What would an increase in blood pressure do
56
What effect would this have on urine production
57
What is the total amount of filtrate formed per minute by the kidneys
Men: ~ 125ml/min
Female: ~120ml/min
This is GFR
58
How often does blood volume get filtered into glomerulus to bowman's capsule?
Every 40 minutes
59
What needs to be reabosrbed in Bowman's Capsule
Water, salts, glucose
60
How much of formative urine (Filtrate) is resbsorbed?
about 99%
61
GFR is directly proportional to what?
Net filtration pressure
62
What happens if GFR is too high
Needed substances cannot be reabsorbed quickly enough and are lost in the urine
63
What happens if GFR is too low
Everything is reabsorbed, including wastes that should be disposed of
64
What are 3 mechanisms that control GFR
- Renal Autoregulation (intrinsic Systems)
- Neural Controls
- Hormal Mechanism (RAAA)
65
What happens when you fail to regulate BP
high BP= blood in urine
low BP= Urine in blood
66
Low BP is vaso..
dilation
67
High BP is vaso...
constriction
68
Under normal conditions renal autoregulation maintains what
a nearly constant GFR
69
When does Juxtaglomerular apparatus (JGA) (Intrinsic 2) kick in
When GFR is high and intrsinic 1 is active but can't do enough to regulate GFR
70
What is Tubular glomerular (JGA) (Intrinsic 2)
Involves Juxtaglomerular apparatus (Macula densa cells) and the distal loop of henle
71
What are extrinsic controls under stress
- Norepinephrine/epi is released by SNS
- Epi is released by adrenal medulla
- Afferent Arterioles constrict and filtration is inhibited
72
When is renin released
With a dramatic drop in blood pressure
73
What triggers renin release
1. Reduced stretch of granular JG cells
2. Direct stimulation of the granular JG cells via norepinephrine/epi by renal nerves
*the pressure reducing causes the cells to act
74
Where does angiotensinogen II travel to become angiotensinogen II
travels in blood to the lungs
75
What are the actions of angiotensinogen II
1. Vasoconstriction of systemic arterioles (Increased BP)
2. Stimulates Aldosterone secretion from adrenal cortex
3. Stimulation of thirst centers in Hypothalamus
4. Stimulation of ADH from posterior pituitary gland
76
What does aldosterone stimulate
Increases sodium, chloride and water by the kidneys, leading to increase in BV and BP
*pee less
77
What does water renention by the kidneys from ADH do
Makes DCT and collecting ducts more permeable to water (increase BV and BP)
78
What is released for High blood pressure
Atrial Natiuretic Peptide (ANP)
79
In response to high blood pressure..
1. Dilates Afferent Arterioles (increase GFR)
2. Increases permeability of glomerulus (increase GFR)
3. ADH release shuts off
4. Decrease in Aldosterone and Renin, both not released with high BP
80
In response to low blood pressure...
1. Constricts Afferent Arterioles (decrease GFR)
2. Decreases permeability of glomerulus (decrease GFR)
3. ADH release decreases
4. Decrease in Aldosterone and Renin
81
Proximal Convoluted Tubule
- Site of reabsorption
- All nutrients, such as a glucose and amino acids, sodium, water and major ions are reabsorbed
- 65% of Na+ and water reabsorbed
- Lots of Active transport occuring
82
Why do the kidneys have mitochondria
as fast as the kidneys make ATP they are using it to get all filtered stuff back into the blood
83
Transport maximum
Tm exists for almost every reabsorbed substance
- Reflects the number of carriers in renal tubules that are available, when there's excess solutes they are secreted in urine
84
Transcellular transport systems are..
specific and limited
85
Osmolarity
The number of solute particles dissolved in 1 liter of water
86
What keeps the solute load of bodily fluids constant at 300 mosm
the kidneys accompanied by the countercurrent mechanism system
87
Countercurrent mechanism
Interaction between the flow of filtrate through the loops of henle and the flow of blood through the vaso recta
88
Loop of Henle Descending loop for countercurrent multiplyer
Reletivley impermeable to solutes but permeable to water
89
Loop of Henle Ascending loop for countercurrent multiplyer
permeable to solutes but impermeable to water
90
What is renal clearance
The volume of plasma that is cleared of a particular substance in given time
91
What do renal clearance tests determine
GFR
detect glomerular damage
follow progress of existing renal disease
92
What is inulin
A substance that cannot be broken down
so all inulin that comes in all comes out
93
What is chronic renal disease
defined as GFR< 60ml/min for 3 months
94
what occurs when GFR< 60ml/min for 3 months
the filtrate formation decreases, nitrogenous wastes accumulate in blood, pH becomes acidic
95
Define renal failure
when GFR <15ml/min
96
What makes urine yellow
urochrome
97
What can indicate bacterial infection in urine
cloudy urine
98
What can change the color of urine
- drugs
- vitamin C supplements
- Diet
99
Odor in urine
- Fresh urine smells a little
- Standing urine develops ammonia odor
- Drugs and foods can alter the smell of urine
100
What is specific gracity
Ranges from 1.001 (dilute)- 1.035 (concentrated)
- Higher value, more salts
- Dependent on solute concentration
101
What is the chemical composition of urine
95% water
5% solutes
102
Nitrogenous Wastes in urine
- Urea: From AA breakdown (largest solute componet)
- Uric acid: From nucleic acid metabolism
- Creatinine (metabolite of creatine phosphate)
103
What does GFR match in the blood
creatinine
104
What can be used to measure kidney health if patient is allergic to inulin
Inject Creatinine
