Brainscape's Knowledge GenomeTM

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


See full index

Embryology > Urogenital system > Flashcards

Urogenital system Flashcards

1
Q

where do the urinary and genital system develop from?

A

common mesodermal ridge (intermediate mesoderm)

along posterior wall of abdominal cavity

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

where do the excretory ducts of the urogenital systems enter initially?

A

common cavity - cloaca

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

development of the kidney systems and the importance of each

A

slightly overlapping in cranial-to-caudal sequence

pronephros, mesonephros, metanephros

first is rudimentary/non-functional, second functions for short time, third forms permanent kidney

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

when do pronephros first appear?

A

at beginning of 4th week

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

how do pronephros first appear?

A

7-10 solid cell groups in cervical region

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

what do pronephros form?

A

vestigial excretory units, nephrotomes, that regress before more caudal ones are formed

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

when do pronephros disappear?

A

end of 4th week

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

where are the mesonephros derived from?

A

intermediate mesoderm from upper lumbar (L3) segments

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

what appears within the mesonephros? when?

A

early in 4th week, first excretory tubules of mesonephros appear

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

development of excretory tubules of the mesonephros

A

lengthen rapidly, form an S-shaped loop, acquire a tuft of capillaries that will form a glomerulus at medial extremity

form Bowman’s capsule

laterally, the tubule enters the longitudinal collecting duct - mesonephric/Wolffian duct

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

what happens in the middle of the second month in kidney development?

A

mesonephros forms large ovoid organ on each side of the midline

urogenital ridge formed by both organs from gonad on its medial side

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

what is the urogenital ridge?

A

ridge formed by the gonad and ovoid organ formed by the mesonephros in 2nd month

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

disappearance of tubules of mesonephros

A

while caudal tubules are still differentiating, cranial tubules and glomeruli show degenerative changes - most disappear by end of 2nd month

in male - few caudal tubules and mesonephric duct persist and participate in formation of genital system

disappear in female

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

when does the metanephros appear?

A

5th week

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

where do the metanephros excretory units develop from?

A

metanephric mesoderm

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

where do collecting ducts of the permanent kidney develop from?

A

uretic bud - outgrowth of the mesonephric duct close to its entrance to the cloaca

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

development of the uretic bud

A

outgrowth of the mesonephric duct close to its entrance to the cloaca

bud penetrates the metanephric tissue - moulded over its distal end as a cap

dilates to form the renal pelvis

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

where does the primitive renal pelvis develop from?

A

uretic bud dilating

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

what does the renal pelvis split into?

A

cranial and caudal portions - future major calyces

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

development of the major calyces

A

forms 2 new buds each while penetrating metanephric tissue

subdivide until 12+ generations of tubules have formed

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

how are the minor calyces formed?

A

tubules of the second order enlarge and absorb those of the 3rd and 4th generations

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

development of the 5th and successive tubules of the major calyces

A

elongate considerably and converge onto the minor calyx, forming the renal pyramid

23
Q

how is the renal pyramid formed?

A

the 5th and successive tubules of the major calyces elongate and converge onto the minor calyces

24
Q

what is each newly formed collecting tubule covered by?

A

metanephric tissue cap

25
Q

development of the metanephric tissue cap

A

form renal vesicles under inductive influence of tubule

give rise to small S shaped tubules

capillaries grow into the pocket at one end of the S and differentiate into the glomeruli

26
Q

what forms the nephrons?

A

tubules and glomeruli

27
Q

where does Bowman’s capsule form?

A

proximal end of each nephron

28
Q

formation of proximal convoluted tubule, loop of Henle and distal convoluted tubule

A

distal end forms an open connection with one of the collecting tubules, establishing a passageway from Bowman’s capsule to collecting unit

continuous lengthening of the excretory tubule

29
Q

what sources does the kidney develop from?

A

metanephric mesoderm, which provides excretory units

uretic bud - gives rise to collecting system

30
Q

when are nephrons formed until?

A

birth

31
Q

how many nephrons are there in each kidney at birth?

A

1 mill.

32
Q

when does urine production begin?

A

early in gestation

after differentiation of glomerular capillaries

33
Q

when do glomerular capillaries begin to appear?

A

10th week

34
Q

what is the appearance of the kidneys at birth?

A

lobulated

lobulation disappears during infancy due to further growth of nephrons (no increase in their number)

35
Q

epithelial-mesenchymal interaction in kidney development

A

epithelium of uretic bud from mesonephros interacts w/ mesenchyme of metanephric blastema

36
Q

what does mesenchyme of the metanephric blastema express?

A

WT1

37
Q

what is WT1? what does it do?

A

transcription factor

makes tissue competent to respond to induction by the uretic bud

38
Q

what does WT1 regulate the production of? what does this do?

A

glial-derived neurotrophic factor (GDNF)

hepatocyte growth factor (HGF or scatter factor)

by mesenchyme - stimulate branching and growth of uretic bud

39
Q

what are the receptors for GDNF and HGF?

A

tyrosine kinase receptors RET

MET

synthesised by epithelium of uretic buds

40
Q

how do uretic buds induce the mesenchyme?

A

fibroblast growth factor 2 (FGF2)

bone morphogenetic protein 7 (BMP7)

41
Q

what do FGF2 and BMP7 do?

A

block apoptosis and stimulate proliferation in the metanephric mesenchyme while maintaining production of WT1

42
Q

what mediates the conversion of the mesenchyme to an epithelium for nephron formation?

A

uretic buds

expression of WNT9B and WNT6, which upregulate PAX2 and WNT4 in the metanephric mesenchyme

43
Q

what do PAX2 and WNT4 do?

A

PAX2 promotes condensation of the mesenchyme preparatory to tubule formation

WNT4 causes the condensed mesenchyme to epithelialize and form tubules

44
Q

modifications in extracellular matrix in kidneys

A

fibronectin, collagen I and collagen III are replaced w/ laminin and type IV collagen (epithelial basal lamina)

45
Q

what cell adhesion molecules are synthesised in the kidneys?

A

syndecan and E-cadherin

essential for condensation of the mesenchyme into an epithelium

46
Q

position of the kidney

A

initially in pelvic region, shifts to a more cranial position in the abdomen

47
Q

what is the ascent of the kidney caused by?

A

diminution of body curvature and growth of the body in the lumbar and sacral regions

48
Q

change in vascularisation of metanephros

A

in pelvis, it receives its arterial supply from a pelvic branch of the aorta

in its ascent, it’s vascularised by arteries originating from aorta at higher levels

lower vessels usually degenerate, but some remain

49
Q

function of the kidney

A

definitive kidney formed from metanephros becomes functional near the 12th week

urine passed into amniotic cavity, mixes w/ amniotic fluid
fluid is swallowed by fetus and recycles through kidneys

not responsible for the excretion of waste products - the placenta does this

50
Q

when does the cloaca divide?

A

4th-7th weeks

51
Q

what does the cloaca divide into?

A

urogenital sinus anteriorly and the anal canal posteriorly

52
Q

what is the urorectal septum?

A

layer of mesoderm between primitive anal canal and the urogenital sinus

53
Q

what will the tip of the urorectal septum form?

A

perineal body - site of insertion of several perineal muscles

Embryology (2 decks)

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