Brainscape's Knowledge GenomeTM

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


See full index

Urogenital Histology > Kidney & Urinary Passages > Flashcards

Kidney & Urinary Passages Flashcards

1
Q

The cortex of kidney contains…….while medulla contains……

A

Renal corpuscles, medullary rays, convoluted tubules, peritubular capillaries
Collecting tubules, loops of Henle, blood capillaries

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

The apices of pyramids are called…….they are perforated by……this region is known as…..

A

Renal papillae
Duct of Bellini
Area cribrosa

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

Duct of Bellini is formed by……..

A

Union of several medullary collecting tubules

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

Medullary rays are gormed of…..

A

Clusters of collecting tubules & ducts

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

Short nephron are………, while long are…..

A

Cortical (85%)
Juxtamedullary (15%)

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

The renal corpuscle diameter is…….

A

200 um

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

Describe the composition of parietal layer of Bowman’s capsule

A

Formed of simple squamous epithelium supported by basal lamina, at the urinary pole it changes into cuboidal epithelium of PCT.

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

Cell body of podocyte & 1ry processes are separated from glomerular BM by……which is filled by…..

A

Subpodocytic space
Glomerular filtrate

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

The interdigitating feet are separated by………

A

Elongated filtration slits (20-30 nm) covered by zipper-like slit diaphragm (5-7 mm thick)

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

Describe the filtration slit diaphragms

A

They are modified are modified & specialized occluding junctions between cell membrane of the pedicles on each side of the filtration slit acting as molecular seive, holds back macromolecules of intermediate molecular weight.

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

List functions of podocytes

A
  1. They are involved in synthesis of the glomerular BM
  2. They share in formation of blood renal barrier
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the function of endothelium in renal corpuscle

A
  1. These cells hold back all blood cells & platelets
  2. Act as a barrier for macromolecules whose diameter exceeds size of fenestrae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

List the layers of glomerular basement membrane & their components

A
  1. Lamina rara interna: laminin & fibronectin which bind integrins of podocytes
  2. Lamina densa: type IV collagen & large proteoglycgans (heparan sulphate)
  3. Lamin rara externa: like 1 bind endothelium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe function of glomerular basement membrane

A
  1. Lamina densa (physical filter): traps molecules with high molecular weight
  2. Lamina rarae: contain -ve charged molecules that repel plasma proteins as albumin preventing their passage.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the structure & function if blood renal barrier

A

1,. Fenestrated endothelium, not closed by diaphragm, prevents passage of blood cells & platelets
2. Glomerular BM, prevents passage of large proteins (albumin) & organic anions.
3. Filtration slits between minor processes of podocytes closed by slit diaphragms hold back small proteins & oragnic anions

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

Describe composition of initial glomerular filtrate

A

Similar to that of plasma ex that it contains very little protein

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

List causes of high hydrostatic pressure in glomerular capillaries

A
  1. Overall diameter of Afferent arteriole is larger than that of efferent while luminal diameter is similar in both bec aff has thicker media
  2. These arterioles possess smooth muscle fibers in their media that maintain a high hydrostatic pressure along their length
  3. No venous drainage for renal corpuscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the site of intragomerular mesangial cells

A

They are found in between capillaries in areas where basal lamina forms a sheath around 2 or more capillaries. In these areas the basement membrane does not completely surround each capillary.

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

Describe the structure of mesangial cells

A

LM: they are stellate in shape with multiple cytoplasmic processes that penetrate between the endothelial cells to reach the capillary lumen & show basophilic cytoplasm & darkly stained nucleus
EM: they contain many lysosomes, myosin-like filaments & lipofuscin granules

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

List functions of mesangial cells

A
  1. Structural support to glomerular capillaries
  2. They are resposible for continuous turnover of BM, by removal of old one & formation of new BM
  3. They may act as macrophages since they clean the BM from particulate matter as normal & pathological immune complexes
  4. Synthesize ECM
  5. They are contractile cells resembling vascular pericytes
  6. Regulate glomerular blood flow in response to BP changes as they have receptors for Ang II & ANF
  7. Produce mediators as cytokines & prostaglandins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The longest part of nephron is…..

A

PCT

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

Describe LM structure of PCT

A
  1. Lined by simple cuboidal epithelium, lumen is often narrow
  2. In cross-section each tubule is lined by 3-5 cells with indistinct lateral cell boundaries
  3. Each cells contains rounded basal nucleus & deeply acidophilic cytoplasm with basal striations
  4. Apical parts show PAS +ve brush borders
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe EM structure of PCT

A
  1. Apical microvili with canaliculi in-between to absorb macromolecules
  2. Lateral borders show extensive & complex interdigitation
  3. Na pump is basolateral membrane for active transport, it has basal infoldings with elongated mitochondria lying between them, it has basal infoldings which inc surface area
  4. Numerous mitochondria, supranuclear golgi, numerous pinocytotic vesicles indicating pinocytosis endocytosis & vesicles which contain small reabsorbed proteins that will be degraded in lysosomes with AA release in circulation.
24
Q

Describe function of PCT

A
  1. Transcellular reabsorption of water, Na, Cl, Ca, PO4 by passive & active transport.
  2. Reabsorb all glucose & AAs by active transport
  3. Reabsorb plasma proteins by pinocytosis via receptor mediated endocytosis
  4. Actively excrete creatinine, certain dyes & drugs as penicillin
25
Q

List components of Loop of Henle with lining of each

A
  1. Initial short thick descending limb represents straigt part of PCT lined by cuboidal epithelium
  2. Thin descending limb lined by simple squamous epithelium shorter in cortical nephron
  3. Thin ascending limb lined by sse absent in cortical
  4. Thick long asceding limb lined by sce represents beginning if DCT
26
Q

Mention portions of DCT

A
  1. Straight portion continuation of ascending thick loop of Henle
  2. Macula densa: in close association with vascular pole of renal corpuscle of same nephron
  3. Convoluted portion till proximal end of collecting tubule
27
Q

Describe LM picture of DCT

A

Its lining epithelium is simple low cubical, wider lumen than PCT lined by 5-8 cells, each DCT contain fewer mitochondria making them less acidophilic than PCT with distinct lateral boundaries & striated basal parts, also has rounded central nucleus.

28
Q

Describe EM picture of DCT

A
  1. Show less microvilli and less extensive lateral interdigitations comapres to PCT
  2. More developed basal infoldings than PCT, these infoldings form compartments of cell membrane with elongated large mitochondria lying in them
  3. No apical canaliculi & pinocytotic vesicles
29
Q

List functions of DCT

A
  1. It controls total content of salt & water in the body & makes adjustments in acid-base balance
  2. It reabsorbs water (ADH) & sodium (aldosterone)
  3. Excretes sodium & potassium controlled by ANF
  4. Macula densa acts as monitor for osmolarity & volume of the filtrate in DCT & stimulates juxtaglomerular cells to secrete renin
30
Q

Cortical/medullary collecting tubules are formed of…&…..

A

Light (pricipal) & dark (intercalated) cells

31
Q

Describe structure of light cells

A

LM: numerous cubical cells with pale cytoplasm & central rounded nuclei with distinct cell boundaries
EM: few mitochondria, sparse microvilli, & a 1ry cilium among them, the lateral margins of adjacent cells show no interdigitations, basal cell membrane has numerous infoldings, has receptors for ADH & many aquaporins which are integral membrane proteins most of them are stored in cytoplasmic vesicles.

32
Q

Describe structure of dark cells

A

LM: few cubical cells with central rounded nuclei
EM: abundant mito, numerous apical projecting apical folds, intercalated cells are involved in secretion of H or HCO3

33
Q

Ducts of Bellini open into…..& lined by……

A

Minor calyx
Tall columnar principal cells

34
Q

List function of collecting tubules

A
  1. They conduct & concentrate urine under control of ADH & aldosterone
  2. Maintain acid base balance as they secrete H+ or HCO3-
35
Q

Describe composition of renal interstitium in cortex

A

Sparse CT with thin collagen bundles and fibroblast-like cells+mononuclear cells which may be phagocytic

36
Q

Describe composition of renal interstitium in medulla & its function

A

CT is more extensive contains medullary interstitial cells which are fibroblast like cells and they are rich with small lipid droplets for synthesis of prostalglandins & prostacyclin
F: secrete medullipin I hormone which is converted in liver to medullipin II causes VD & dec BP

37
Q

List cells secreting hormones in kidney

A
  1. Juxtaglomerular cells secrete renin
  2. Medullry interstitial cells secrete medullipin I
    (Dual control on BP)
  3. Endothelial cells of peritubular capillaries secrete erythropoietin. It alsohydroxylates vitamin D3 to it active form.
38
Q

Describe the structure of macula densa

A
  1. Formed of closely packed talk columnar cells with oval apinal nuclei
  2. Don’t have basal infoldings
  3. Numerous microvilli
  4. Thin or absent BM so they are in direct contact with juxtaglomerular cells & lacis cells
  5. They have processes that pass through the lacking BM towards juxtaglomerular cells
  6. The Golgi apparatus is situated basally
  7. They contain few & widely distributed mitochondria
39
Q

Describe function of macula densa

A
  1. It has a secretory function that influences activity of juxtaglomerular cells by detecting ionic content & water volume
  2. Macula densa regulates glomerular filtration by detecting Cl- ion content in tubular fluid producing signals that cause constriction of aff arterioles
40
Q

Lacis cells are joined by……..

A

Gap junction

41
Q

Describe the structure of juxtaglomerukar cells

A

They are modified smooth muscle cells in the afferent arteriole, may be found in eff
LM: have rounded nuclei instead of elongated, their cytoplasm contains PAS +ve granules
EM: abundant rER & well-developed Golgi apparatus & secretory granules with protease renin

42
Q

Relate the structure of juxtaglomerular cells to their function

A
  1. In close contact with blood in lumen bec the internal elastic lamina is thin or absent
  2. Close contact with macula densa present in DCT
  3. Innervated by adrenergic nerve fibers & sympathetic stimulation inc their rate of secretion of renin
43
Q

Describe the function JG cells

A

Play a key role in regulation of BP, they secrete renin in response to fall in blood pressure by detecting:
1. Degree of stretch of wall of afferent arterioles
2. Cl- conc of urinary filtrate that reaches DCT, this conc drops when there is dec BP, macula densa monitors these changes & stimulates juxtaglomerular cells to secrete renin
3. Impairment of renal blood flow
4. Sympathetic stimulation
Renin acts on angiotensinogen produced in liver to form Ang I converted to Ang II by ACE in endothelium of lung capillaries.

44
Q

Peritubular capillaries arise from…….& nourish……..

A

Efferent arterioles of cortical nephrons
PCT & DCT

45
Q

…….arise from efferent arterioles in medulla, then drain into……which then drain into….

A

Arteriola rectae
Venulae recta
Arcuate vein

46
Q

Capillaries of outer cortex & capsule form…..veins which empty into……

A

Stellate
Interlobular veins

47
Q

List sources of non-glomerular blood supply to the kidney

A
  1. Terminal branches of interlobular arteries
  2. Capsular arteries
  3. Shunt between aff & eff
  4. Arteriolae rectae which arise from arcuate of interlobular arteries
48
Q

……arteriole is more comtractile

A

Efferent

49
Q

Describe general structure of urinary passages

A
  1. Mucosa: formed of transitional epithelium resting on CT
  2. Musculosa: formed of smooth muscle fibers
  3. Adventitia: formed of areolar CT
50
Q

Describe general structure of transitional epithelium

A

It is 5-6 cells thick:
-Single layer of small basal cells resting on very thin BM
-An intermediate region containing from one to several layers of cuboidal or low columnar cells
-A superficial layer of large umbrella cells called Facet cells

51
Q

Describe the structure of Facet cells

A
  1. They are large cuboidal cells when the organ is empty & squamous when it is full
  2. May be binucleated
  3. Their luminal surface is convex, apical surface consists of unique asymmetrical unit membrane, where outer leaflet is twice as thick as inner leaflet containing plaques of integral proteins called uroplakins
  4. Have complex occluding junctions together with tight junction which serve as osmotic barrier preventing dilution of the stored urine
  5. The apical cytoplasm contains fusiform vesicles surrounded by thick membrane, they are a reservoir for cell membrane to inc cell surface in full bladder
52
Q

Describe the musculosa of urinary bladder

A

It is thick & formed of smooth muscle fibers, well-developed, run in every direction (without distinct layers) until they approach neck of bladder, they are arranged into outer longitudinal, middle circular & inner longitudinal muscle fibers.

53
Q

Describe the musculosa of ureter

A

Upper 2/3: outer circular & inner longitudinal muscle fibers.
Lower 1/3: outer longitudinal, middle circular & inner longitudinal muscle fibers.

54
Q

With respect the female urethra, its proximal end is lined by….., while distal part is lined by……

A

Transitional epithelium
Non-keratinized stratified squamous epithelium

55
Q

Prostatic urethra is lined by……., membranous is lined by……., spongy is lined by…….

A

Transitional
Stratified columnar epithelium
Stratified columnar e, navicular fossa is lined by non-keratinized squamous epithelium

56
Q

Mention the 2 glands presents in penile urethra

A
  1. Intraepithelial glands, found interspersed in epithelial lining
  2. Glands of Littre: in CT open by short ducts (urethral mucous glands)
57
Q

Prostatic urethra is surrounded by……, while membranous is surrounded by……

A

Outer circular smooth muscle (internal sphnicter)
Skeletal muscle (external sphincter)

Urogenital Histology (3 decks)

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