Brainscape's Knowledge GenomeTM

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


See full index

Phase 1 Flashcards > Skin and kidneys 1 > Flashcards

Skin and kidneys 1 Flashcards

1
Q

Normal proliferation of skin occurs just in what layer? Functions of the skin?

A

The basal layer

Barrier to infection 
Thermoregulation 
Protection against trauma 
Protection against UV 
Vitamin D synthesis
Regulates H20 loss
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

3 basic layers of the skin?

A

Epidermis, dermis and subcutaneous tissue

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

What is the epidermis also known as? Made up of what 2 things? Corneo-desmosomes known as what? These increase in what diseases? These decrease when?

A

The stratum corneum
Corneo-desmosomes and desmosomes
Adhesion molecules- keeps the corneocytes together
Ones like psoriasis- striatum corneum thickens
In atopic eczema–> more inflammation

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

Filaggrin produces what factor? What are filled with NMF? Why is NMF also important? What happens to balance the intro of new cells in the basal layer? This involves what?

A

Natural moisturising factor (NMF)
Corneocytes- keeps H2O inside skin
Maintains acidic environment at outer surface
Corneocytes are shed in desquamation
Degradation of extracellular borneo-desmosomes under proteases

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

pH of normal skin? What component keeps water inside the skin cells?

A

5.5

Lipid lamellae

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

What is the brick wall model? What is vitamin D needed to make?

A

Corneocytes= bricks, corneodesmosomes= iron rods and lipid lamellae= cement.
Anti-microbial peptides needed to defend he skin from bacteria and viruses

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

What are skin flare ups? What causes red, itchy and dry skin?

A

Allergens penetrate into the skin, met with lymphocytes which release chemicals that induce inflammation
Red= dilation of blood vessels, itchy= nerve stimulation, dry= skin cells leaking due to lymphocytes activity.

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

What does reduced water retention lead to?

A

The pH will increase–> corneodesmosomes become damaged, so skin barrier breaks down and infection risk increases

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

What happens due to hypercornification during acne? What increases in production? Where does sebum go? Where does it stagnate and causes what?

A

Corneodesmosomes block entrance to hair follicles
Sebum–> greasy skin
Some becomes trapped in the narrowed hair follicle
In follicle pit–> anaerobic conditions so propionic bacteria can multiply

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

What do p.acnes do? What therefore forms? What 2 things can trigger acne?

A

Breakdown triglycerides in sebum into fatty acids– irritation, inflammation and neutrophil attraction
Pus forms and further inflammation
Cosmetics and oily hair gel

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

Level of kidneys? Hilum of R kidney? L kidney? What layer is the renal pyramids in? What layer contains the renal corpuscles (glomeruli and capsules) and tubules?

A

Between T12-L3
L2/ L1
Medulla= 20 upside down pyramids
Cortex

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

What are medullary rays? Give the cortex what appearance?

A

Collection of loop of Henle tubules and collecting ducts that come from nephrons which have corpuscles in outer part of cortex
Striated appearance

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

What things are in the medulla? What thing projects into the renal pelvis?

A

Tubules of loop of Henle, tubules of collecting duct and blood vessels
Tips of the medullary pyramids= purely collecting ducts at this point

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

What level does renal artery come off of abdominal aorta? Divides into what which leads to what? Arcuate arteries travel where and give off what?

A

L1
Segmental arteries–> arcuate arteries
Circumferentially at junction between cortex and medulla–> interlobar arteries

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

Interlobar arteries supply what and divide to form what?

A

Each lobe (medullary pyramid and overlying cortex)–> interlobular arteries–> afferent arterioles

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

What is within a renal corpuscle? Tuft is supported by what cells?

A

Glomerular tuft and bowman capsule

Smooth muscle mesangial cells

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

What is within the glomerular basement membrane? What stain can distinguish mesnagial cells from capillaries?

A 
The capillary and podocyte basement membrane 
PAS stain(stains glycoproteins in basement membrane and mesangial cells in between)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

3 main functions of Mesangial cells?

A

Structural support for capillary and produces extracellular matrix protein
Contraction of this modified smooth muscle reduces GFR
Phagocytosis of glomerular filtration membrane breakdown products

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

2 components involved in the juxtaglomerular apparatus? The endothelium of the afferent arteriole is expanded to form a mass of cells called what? Distal convoluted tubule has expansion of cells known as what?

A

Afferent arteriole and distal convoluted tubule
Granular cells- detect BP and secretes renin due to low BP
The macula dense- detect sodium levels

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

If filtration is slow, more what is absorbed and the macula dense sends a signal to do what?

A

More sodium absorbed–> macula densa sends a signal to reduce the afferent arteriole resistance and increase glomerular filtration

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

3rd group of cells in juxtaglomerular apparatus?

A

Lacis cells

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

Cells of proximal convoluted tubule actively transport how much of Na+ and K+ ions from glomerular filtrate? These cells also absorb what? In what convoluted tubule is there more lysosomes?

A

2/3
The small protein molecules that got through the glomerulus
In proximal than distal

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

What are the loops of Henle supplied by? What passes out of the thin descending limb?

A

A rich vasa recta

Water but not ions- concentrates urine going down

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

What happens going up the thick ascending limb? Where are the vasa recta far from?

A

Ions are actively pumped out of the ascending limb leaving water and waste products
The glomerulus- before blood reached, already lost some O2 carrying. Loop deep in medulla prone to ischemia.

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

Which convoluted tubule is shorter? How does it act to regulate the acid base balance? This is mediated by what hormone?

A

Distal is much shorter than proximal
Secretes H+ ions into it from an intracellular carbonic anhydrase and exchanges urinary Na+ for body K+
Aldosterone

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

Principal cells in collecting ducts respond to what 2 hormones? What do intercalated cells do? What feature makes them look different to the loop of Henle?

A

Aldosterone(exchange Na+ for K+) and ADH (increases insertion of aquaporin-2- mutation in gene–> diabetes insipidus)
Exchanges acid for base- alpha secrete acid and beta secrete bicarbonate
Have a plumper epithelium

27
Q

3 major functions of the kidneys? Each receives what % of cardiac output? Total renal blood flow what value? Total urine flow what value?

A

Endocrine function, maintain balance of salt water and pH and excretion of waste products
20%, 1L/min, 1ml/min

28
Q

Divisions of renal artery? Each nephron has how many capillary beds?

A

Renal–>segmental->interlobular–>arcuate–>interlobular–>afferent–>capillary–>efferent–>peritubular capillary
2 capillary beds

29
Q

What % of plasma filters into Bowman’s capsule? Blood in glomerulus is separated from fluid in Bowman’s space by what 3 layers?

A

20%

Single-celled capillary endothelium, basement membrane and epithelial lining of Bowman’s capsule

30
Q

% of nephrons that are juxtamedullary? % that are cortical? Some cortical nephrons don’t have what?

A

15%, 85%

A Henle’s loop- involved in reabsorption and secretion only

31
Q

What is glomerular filtration?

A

The passage of fluid from the blood into Bowman’s space to form the filtrate

32
Q

Flow of glomerular filtrate?

A

Glomerular capsule–> proximal convoluted tubule–> nephron loop–> distal convoluted tubule–> papillary duct–> minor then major calyx–> renal pelvis–> ureter–> urinary bladder–> urethra

33
Q

What is tubular reabsorption? What is tubular secretion?

A

When the direction of movement is from the tubular lumen to peritubular capillary plasma
Movement in the opposite direction from the peritubular capillary plasma to the tubular lumen

34
Q

What things can pass freely and what can’t and why?

A

Small molecules and ions up to 10kDa e.g. glucose, uric acid, potassium, creatinine can.
Fixed negative charge in basement membrane repels charged anions e.g. albumin

35
Q

Only protein to be found in the urine? Damage can lead to protein leak known as what? What condition can lead to microalbuminuria?

A

Tamm horsfall protein (uromodulin)- produced by the thick ascending limb of the loop of Henle
Nephrotic syndrome
Diabetic nephropathy

36
Q

How do hydrostatic and oncotic pressure differ in Bowman’s capsule and along glomerular capillary?

A

Hydrostatic pressure is constant along capillary but oncotic increases as proteins become more conc
Bowman’s= no oncotic as no proteins

37
Q

Equation for GFR?

A

(Pgc- Pbs)- (Pigc- Pibs)
1st brackets= hydrostatic pressure, 2nd= oncotic pressure
gc= glomerular capillary
bs= Bowman’s space

38
Q

Simplified equation for GFR? What is KF? Average GFR in a 70kg person?

A

KF(Pgc-Pbs-Pigc)
The filtration coefficient- the product of permeability of the filtration barrier and the surface area available for filtration
125ml/min

39
Q

What is GFR determined by? GFR regulated physiologically by what?

A

Net filtration pressure and permeability of the corpuscular membranes, SA available for filtration
Neural and hormonal input to afferent and efferent arterioles

40
Q

What does constricting afferent arterioles do to GFR? Constricting what can have the opposite effect? Simultaneous constriction/ dilation tends to do what to Pgc?

A

It decreases hydrostatic pressure in glomerular capillaries- greater loss of pressure between arteries and capillaries
By constricting efferent arterioles
Leaves Pgc unchanged due to the opposing effects

41
Q

How can GFR be measured? What must this marker substance be? How is the amount of M in fluid calculated?

A

By measuring the excretion of a marker substance (M)
Freely filtered, not secreted/ absorbed in the tubules and not metabolised
Concentration in fluid x volume of fluid

42
Q

How is GFR measured using amount of M in fluid? Entire plasma volume filtered around how many times every day?

A

Um x urine flow rate/ Pm
Um= conc of M in urine
Pm= conc of M in plasma
60 times every 24 hours

43
Q

What is creatinine and where is it produced?

A

A muscle metabolite with constant production- serum conc varies with muscle mass. Some additional secretion by the tubules

44
Q

How the filtration fraction calculated? What is it? Usual value?

A

GFR/ renal plasma flow
The proportion of renal blood flow that gets filtered
0.2% as 40% of blood is cells, so 60% will be plasma, so 120/600

45
Q

What is renal clearance? Equation for clearance of substance M? Values for urea, PAH and glucose compared to GFR?

A

The volume of plasma from which a substance is completely removed by the kidney per unit time (usually a min)
Urine conc x urine volume/ plasma conc
Urea= less as some urea is reabsorbed, PAH= more as secreted by tubules, glucose= 0 as completely reabsorbed

46
Q

What is the constriction and dilation of the arterioles dependent on? 3 stages of constriction? What does this mechanism prevent?

A

Intrinsic property of vascular smooth muscle
Pressure within afferent arteriole rises, stretching the smooth muscle wall, triggering contraction of smooth muscle= arteriolar constriction
An increase in systematic arterial pressure from reaching and damaging the capillaries

47
Q

What is GFR regulated by?

A

The rate at which filtered fluid reaches the distal tubule- macula densa detect reduction in NaCl, triggering renin releases from granular cells

48
Q

How do glucose and phosphate move into proximal tubule cells? What ion moves out into the lumen? What also follows Na+ and other ions?

A

Via secondary active transport along with Na+ diffusing from lumen into cells (NaKATPase pump creates diffusion gradient)
H+ ions
Water via osmosis- across plasma membrane and tight junctions–> interstitial fluid

49
Q

What is formed inside tubular cells by CO2 and H2O? Where does the HCO3- go? H+ goes where? What does H+ combine with? Overall what is reabsorbed?

A

H2CO3 using carbonic anhydrase–> H+ and HCO3-
Via facilitated diffusion into interstitial fluid and into blood
Into lumen via Na/ H+
HCO3- to form H2CO3–> back to CO2 and H2O–> from lumen into tubular cells
Bicarbonate

50
Q

What 3 things are signs of proximal tubule pathology? What condition shows all 3 leaking into urine?

A

Aminoaciduria, glycosuria and bicarbonate wasting

Falcon syndrome

51
Q

What is the transport maximum? Why?

A

Many of the mediated-transport-reabsorptive systems in renal tubule have limit to amounts of material they can transport per unit time
Binding sites on membrane transport proteins become saturated when conc increases to certain level

52
Q

A greater filtration fraction will increase what? Efferent arteriolar constriction reduces?

A

The osmotic pressure in the downstream peritubular capillaries–> more reabsorption
Peritubular capillary hydrostatic pressure

53
Q

Along the entire length of the ascending limb what are reabsorbed? In upper thick portions what happens? What doesn’t happen and why?

A

Na+ and Cl- are reabsorbed from lumen–> medullary interstitial fluid via many channels
Transporters actively cotransport Na+ and Cl-
Water does not follow- ascending limb= impermeable

54
Q

What do diuretics like furosemide inhibit? What does the hairpin-loop structure of the vasa recta minimise?

A

NKCC2 pump on thick ascending part of loop- more water loss as less diffuses out of collecting ducts–> dehydration
Excessive loss of solute from the interstitial by diffusion

55
Q

Where is urea reabsorbed? Urea back into tubular lumen via what?

A

50% in proximal tubule, remaining 50% enters loop of Henle

By facilitated diffusion from medullary interstitium

56
Q

What happens in distal tubule? What cotransporter helps in reabsorbing Na+ and Cl-? Inhibited by what drug?

A

Reabsorbs Na+ in water- impermeable setting

NCC- thiazide

57
Q

What do principal cells in collecting duct have? Aldosterone does what to these? What does ADH bind to? What action results in aquaporin vesicle insertion into apical membrane? Action of intercalated cell?

A 
ENaC
Increases transcription- increases Na+ influx and K+ efflux
Vasopressin receptor(V2R)
Kinase action 
Secretes acid into collecting duct
58
Q

Where is ADH(vasopressin) produced and released by? Half-life of hormone? Also causes what? What things increase and decrease secretion?

A

Made by hypothalamus, secreted by posterior pituitary
15 minutes
Arteriolar constriction
Alcohol= decreases, MDMA and nicotine= increases

59
Q

Decrease in extracellular volume leads to what? Reflex initiated by what in CV system? Decrease rate of firing when? This reflex has a what threshold?

A

Increased aldosterone and vasopressin secretion
Baroreceptors in aortic arch and carotid sinus
When cardio pressures decreases when blood volume decreases
High threshold- less sensitive than osmoreceptor reflex

60
Q

What is thirst stimulated by? What does a low Na+ elicit? Why?

A

By an increase in plasma osmolarity and a decrease in extracellular fluid- stimulate osmoreceptors–> vasopressin secretion
A decrease in GFR–> reduced net glomerular filtration pressure
Low cardio pressure–> vasoconstriction of afferent arteriole–> reduced GFR

61
Q

What cells synthesise and secrete ANP? What does ANP do in the tubular segments? Why is it secreted?

A

Cells in cardiac atria
Inhibits Na+ reabsorption by blocking ENaC’s in collecting ducts, afferent arteriole dilation increasing GFR which excretes more Na+, inhibits aldosterone secretion
More Na+, increases blood volume, atria stretch so is secreted

62
Q

Increases/ decrease in extracellular K+ conc can result in what? % of K+ is reabsorbed in proximal tubule? Increased extracellular K+ conc stimulates what?

A

Abnormal heart rhythms, abnormal skeletal muscle contraction and neuronal AP conduction
90%
Aldosterone release–> more K+ secretion and eliminates excess K+ from body

63
Q

What is parathyroid hormone released in response to? This does what? Also stimulates what?

A

Decreased levels of Ca2+ plasma concs
Directly increases Ca2+ reabsorption in kidneys decreasing urinary Ca2+ excretion
The formation of the active form of vitamin D- stimulates hydrolysis in the kidneys

Phase 1 Flashcards (35 decks)

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