Week 11 Flashcards
(251 cards)
1
Q
What is the peritoneum and what does it line and cover?
A
Continuous serous membrane
Lines abdominal cavity
Covers abdominal organs
2
Q
How many layers of mesothelium is in the peritoneum? What is between the layers?
A
2
potential space - peritoneal cavity
3
Q
What is contained within the peritoneal cavity usually?
A
peritoneal fluid secreted by mesothelium
allows layers to slide over each other
4
Q
functions of the peritoneum?
A
supports viscera
provides pathways for blood vessels and lymph to travel to and from the viscera
5
Q
what are the 2 layers of the peritoneum?
A
parietal peritoneum
visceral peritoneum
6
Q
what does the parietal peritoneum line?
A
internal surface of the abdominopelvic wall - closest to skin
7
Q
where is the parietal peritoneum derived from?
A
somatic mesoderm in embryo
8
Q
what is the parietal peritoneum nerve supply? what does this result in (pain)?
A
same somatic nerve supply as region of abdominal wall that it lines
pain is well localised
9
Q
what is the parietal peritoneum sensitive to?
A
pressure
pain
laceration
temperature
10
Q
where does the visceral peritoneum cover?
A
majority of abdominal viscera (organs) by invagination
11
Q
what is visceral peritoneum derived from?
A
splanchnic mesoderm in embryo
12
Q
what nerve supply does visceral peritoneum have? what does this mean?
A
same autonomic nerve supply as viscera it covers
pain is poorly locailsed
13
Q
what is visceral peritoneum sensitive to?
A
sretch, chemical irritation
14
Q
what is pain from the visceral peritoneum referred to? what are these supplied by?
A
dermatomes
same sensory ganglia and spinal cord segments as nerve fibres innervating viscera
15
Q
what are intraperitoneal organs?
A
spleen
stomach
liver
16
Q
what are retroperitoneal organs? what specific organs are thee?
A
not related to visceral peritoneum and only overs anterior aspect
oesophagus, rectum, kidneys, some duodenum, descending colon, pancreas, adrenal glands, proximal ureters, renal vascalature
17
Q
where are kidneys found? what covers them?
A
T12-L3
ribs 11 and 12
18
Q
why is the right kidney lower than the left?
A
liver displaces kidney
19
Q
functions of kidney?
A
filters waste
produces urine
regulate blood pressure, ions, pH, osmolarity, volume, glucose level
20
Q
which hormones does the kidney produce?
A
calcitrol
erythropoeitin
21
Q
function of calcitrol?
A
raises blood calcium levels by increasing absorption from the gut, kidney, and simulation of release from bones
22
Q
function of erythropoitin?
A
secreted in response to hypoxia or low blood glucose, increases RBCs
23
Q
what is in the hilum of the kidney?
A
renal artery
renal vein
ureter
24
Q
what is within the cortex of the kidney?
A
supporting tissue
glomeruli, bowmans capsule, convuluted tubules
25
what is the medulla of the kidneys function?
functional tissue - loop of henle and collecting tubules
renal pyramids
filtering and production of urine and passes urine to ureters
26
what are nephrons? composition?
functional unit
renal corpusle and tubules
27
what is the renal corpuscle composed of?
glomerulus and bowmans capsule
28
glomerulus structure and function?
network of capillaries
filters blood and passes it to bowmans capsule
29
bowmans capsule function?
collects blood from glomerulus and filters blood from afferent arteriole
30
4 steps in bowmans capsule?
filtration
reabsoprtion - into peritubular capillaries, useful subtsances taken back into body by efferent arteriole
secretion - filtration not taken up by efferent arterole put back into bowmans capsule
excretion - waste products taken to urinary bladder for excretion
31
what are the renal tubules composed of?
proximal convuluted tubule
loop of henle
distal convuluted tubule
32
what happens in PCT?
fluid passed to peritubular capillaries for resprption
rest of fluid passed to loop of henle
33
loop of henle function?
acts as concentration gradient for fluids and electrolytes
reabsorbs water
34
where does DCT pass to?
renal medulla then papillary duct then ureter
35
where is renal corpuscle mostly found?
cortex
36
function of interlobar arteries in kindyes?
supply renal lobes
37
what supplies the cortex of kidneys?
cortical blood vessels
38
how does blood get from medulla to ureter?
pyramids in medulla have papilla at tip
these form minor calyxys draining medullary pyramid which join to form major calyx
multiple major calyxs form renal pelvis which connects to ureter
39
what are arcuate blood vessels?
small blood vessels from interlobar arteries between cortex and medulla
40
function of psoas major?
muslce - helps with hip flexion
41
what is horseshoe kidney? when is it more common? what can it cause? why does this happen?
where 2 kidneys fuse at lower end of abdomen/upper pelvis in utero
more common in boys
lead to UTI
kidneys cant rise to where theyd usually be
42
what is a FAST scann used for? what type of scan is it?
ultrasound for identifying blood around abdominal organs
can identify blood or pus from infection
43
what is haemoperitoneum?
blood around abdominal organs
44
what is perisplenic?
blood around the spleen
45
what is the pouch of morrison?
potential space between kidney and liver
46
what are renal arteries branches of? where are they found?
branches of aorta
behind renal veins
47
where do renal veins drain into?
inferior vena cava
48
differences between R and L renal veins?
left is longer and lies over renal artery
49
function of phrenic veins?
drain the diaphragm
50
where do the R and L gonadal veins drain?
R - directly to IVC
L - left renal vein then IVC
51
what do suprarenal arteries supply?
suprarenal gland
adrenal gland
52
what type of mutation is polycystic kidney disease?
autosomal dominant
53
what does polycystic kidney disease cause any why?
renal failure
many cysts form in kidneys
high parencymal loss - nephrons
54
symptoms of polycystic kidney disease?
raised blood pressire
headaches
abdominal pain
55
function of ureters?
transport urine to bladder by peristalsis (contraction of smooth muscle)
56
what can ureters be blocked by? where?
kidney stones
pelvouteric junction
pelvic brim
trigone
57
where can ureters pass UTIs to?
kidneys
58
what is the trigone?
triangular area of bladdder where uteric orifices are superior and urethra is inferior
59
what muscle is the urinary bladder composed of?
detrusor smooth muscle
60
function of bladder?
stores urine and helps remove it from the body
61
why is the detrusor muslce orientared in many directions?
helps with contraction and relacation in expanding and shrinking dependent on amount of urine present
62
what is uretric meatus?
where ureters enter in bladder
63
why are male gonads external?
to regulate temperature
64
layers of the bladder?
detrusor muscle (external)
submucosa
lamina propira
transitional epithelium
65
vans deferens function?
connects testes to urethra to carry sperm out
66
what is the coat of the testes called?
tunica albugenia
67
what is the cremaster muscle?
striated muscle determining the height of the testes
contraction raises testes towards body
68
where do testes begin development? when do they descend into the scrotum?
in abdomen
in 7th month in utero
69
which 2 glands are in the testes?
exocrine - sperm cells
endocrine - testosterone
70
2 tunics of testes?
tunica vaginalis - outer
tunica albuginea - inner
71
how many lobules are in the tunica albuginea?
200-300
72
how many seminiferous tubules are in each testes lobule?
1-4
73
route of sperm transit in the testes?
seniniferous tubules
straight tubules
rete testes
efferrebt ductules
epididymis
74
where is sperm produced?
seminiferous tubules
immature
75
where do sperm cells mature?
epididymis
76
how much sperm is produced per day? how long do they live in the female tract?
60 million
48hrs
77
what is cryptorchidism? what happens if its bilateral? where is it mostly found?
maldescent of testes
infertility
3% full term infants
90& premature babies
78
what is route of where testes descend called?
internal inigual ring
79
3 places testes can be stuck?
abdominal
inigual
prescrotal
80
which 2 ways can testicular cancer be caused?
germ cell tumors 95%
sex cord stromal tumors 5%
81
what age is testicular cancer most prevalent?
men in 20s
82
what is a varicocoele caused by? appearance?
dilation of pampiniform venous plexus - varicose vein dilation
obstruction of testicular vein
bag of worms
83
what is a hydrocoele caused by? examination?
accumulation of fluid in tunica vaginalis
penslight examination = translucent scrotum
84
3 parts of male urethra?
prostatic
membranous
pendulous
85
parts of prostatic urthra?
urethral crest
urethra
prostatic utricle
sphincter urethrae
86
structure and function of urethral crest?
long fold in posterior wall of urethra
can stop passage of sperm into bladder
87
function of prostatic utricle?
origin of where vagina and uterus would have developed from
88
function of sphincter urethrae?
external sphincter controlling urine expulsion
voluntary
89
what is in the membranous urethra? function?
cowper glands
secrete glycoproteins in mucus during sexual arousal
lubrictaes urethra and penis
helps remove debris and dead cels
neutralises acidity in urethra
90
function of bulborethral glands?
produce glycoproteins
91
function of prostate gland?
biggest accessory gland
produces enzymes to break down proteins
maintains semen in fluid state
stops clotting of semen
92
where is prostate found?
inferior to bladder neck
above externak urethral sphincter
93
what can you feel when performing rectal exam? why is this important?
prostate
examining enlarged prostate - benign prostatic hyperplasia , prostatic cancer
94
function of pubis?
links hip bones
95
where is uterus usually found?
above and behind bladder
usually anteverted
96
4 ways uterus can sit?
anteverted (forward) and anteflexed (fundus forward relative to cervix)
retroflexed (fundus backwards)
retroverted (oriented backward)
97
function of fimbrae?
encourages eggs to move into uterine tube
98
function of round ligament?
maintains anteflexion of uterus (fundus forward)
99
function of broad ligament?
acts as mesentery
minor role in keeping uterus forward
100
function of suspensory ligament? where does it connect to?
contains blood supply of ovaries
connexts to anterior abdominal wall
101
function of ovarian ligament?
connects ovary and lateral aspect of uterus
102
function of rectouterine pouch?
double fold of peritoneum between rectum and back wall of uterus
infection and fluids can accumulate
inferior
103
what is a culdocentesis?
collection of fluid extracted from rectouterine pouch
104
when should baby usually turn?
by week 34
should be by week 36
105
how common is ectopic pregnancy? where is most common pouch? what can it lead to?
1 in every 80-90
ampulla
can lead to rupture and fluid and blood in pouch of douglas (rectouterine pouch)
106
What is online identity?
Representation of who you are based on your internet use of social media and websites
107
What is digital footprint?
Traceable digital activity of each person on the internet
108
What is digital reputation?
Behaviour in online social media forums
109
What is unconscious bias?
Making quick judgements and assessments of peoiple without realising
110
What are biases influenced by?
background
cultural environment
personal experiences
111
Why is there smooth muscle in bladder?
allows volume changes
112
What is activity of detrusor muscle affected by?
reflexes
113
what triggers bladder contraction?
passive stretch of bladder wall
114
How can you investigate the bladder?
Multibarrel catheter
Allows fluid to fill the bladder or removed from bladder at controlled rate
Allows pressure to be measured at several sites simultaneously
115
How do you use multibarrel catheter?
1. place one opening in the bladder to allow direct filling and measure bladder pressure
2. inflate balloon to close off urethra and hold catheter in place
3. position second opening in urethra to measure spincter pressure
4. fill bladder and record pressure to establish bladder compliance/stifness
5. as bladder fills watch for signs of bladder wall contraction and spincter contraction
116
where would you measure pressure in bladder?
inside bladder
external spincter
urethra
117
when is there no flow in the bladder?
spincter pressure or urethral pressure is more than seminal vesicle pressure
118
when is fluid released from bladder?
seminal vesicle pressure higher than spincter/urethral pressure
119
how do males have good ability to not urinate?
strong band of skeletal muscle around urethra delivering high pressure to close off flow
120
why do women have a weaker continence? when can it be damaged?
less skeletal muscle around external spincter
damage during childbirth
121
what happens in storage phase of bladder?
low pressure in bladder during filling - bladder wall and external spincter relaxed
no flow in urethra, urethral pressure > bladder pressure
sensations develop then spincter contracts to maintain continence
122
what happens in voiding phase in bladder?
urge then vluntary voiding
bladder contracts and urethra adn spincter relax. bladder contracts and raises pressure so its higher than urethral pressure
123
what is the innervation from sympathetic nervous system into bladder?
L1, L2
bladder wall and internal spincter
124
what is the innervation from parasympathetic nervous system into bladder?
S2, S3, S4
bladder wall
125
what is the innervation from somatic nervous system into bladder?
S2, S3, S4
sensory and motor to external spincter
126
what are afferent innervations of bladder?
- sensory fibres sense stretch of bladder wall, these run in the hypogastic nerve and enter cord in upper lumbar roots
- sensory fibres near urethra sense flow of urine
- skeletal muslce sensory fibres in external spincter
127
what are efferent innervations of bladder?
- parasympathetic to detrusor
- sympathetic to internal spimcter
- somatic to external spincter
128
what happens to fibres in storage phase of bladder control?
- sympathetic effects suppresses contraction of bladder
- fibres of hypogastric nerve suppress detrusor contraction
- somatic fibres in the pudendal nerve control external spincter
129
what happens to fibres in voiding phase of bladder control?
parasympathetic fibres in pekvic splanchnic nerve cause detrusor to contract
somatic fibres less active
130
what is reflex control in bladder?
via centres in sacral cord and pons
pons centre coordinates with higher centres
131
what are sensations accompanying bladder filling?
first sense of fullness
sense of filling
fullness
desire to urinate
discomort
pain
132
what do bladder sensations depend on? what are sensations supported by? what are unpleasant sensations linked to?
rate of filling
supported by larger myelinated fibres and snalller unmyelinated fibres
smaller fibres
133
when are reflexes dominant in bladder control?
alcohol, sleeping, CNS issues
134
what happens when theres reduced reflex activity in bladder?
may retain small volume of fluid meaning bacteria can accumulate
135
what is normal volume pressure relationship in bladder?
fill slowly to 375 ml then reflex contractions start then stop
136
what happens in neurogenuc bladder?
contraction starts at lower volume due to increased reflex activity
voiding more frequent
137
what is an atonic bladder?
pressure rises slowly without volitional voiding as no relfexes
138
what happens if prostate compresses urethra?
prevents full emptying of bladder and more frequent voiding
139
what is screening?
test offered to asymptomatic person to detect those who have high probability of disease
not diagnostic
140
what technique does cervical screening programme use?
early disease detection - discovers and treating conditions which have produced pathological changes but not reached a stage where medical aid is required
141
name first 5 principles of early disease detection?
- condition should be important problem for individual/community
- accepted treatment for patients and disease
- diagnosis/treatment facilities available
- recognisable latent/early stage
- suitable test/exam
142
last 5 principles of early disease detection?
- test acceptable to population
- natural history of disease understood
- policy exists on who to treat as patients
- case findign should be continuing process
- benefits should outweigh harm
- minimise potential risks of screeing
- should have option to opt out
143
why have death rates of cervical cancer fallen?
improvemnts in treatment
earlier detection of disease
144
how are carvical cancers treated?
- first staged with examination/pathology/radiology
- discussed at MDT
- small cancers at outpatient clinic
- larger tumors at radial hysterectomy
- inoperable with chemo/radiotherapy
145
what happens if abnormaility detected in screening?
biopsy allows diagnosis
patients in cervical screening referred to colposcopy clinic
146
what happens in cervical smear test?
brush removes cells from cervix
transferred to pot of preservative
tested for HPV/cytology
147
what does a test being acceptable to the population mean?
depemds on percieved risk and inconvenience of test
148
what is scottish cervical call recall system?
generates invitations for women to attend smear test
25-65 every 5 years
149
what is underlying cause of most cervical cancers?
HPV
persistant HPV infection can cause cell changes which can progress to cancer
150
risk factors for cervical cancer?
smoking
immosuppression
multiple sexual partners
151
what type of viruses are HPV?
DNA viruses
high risk and low risk
152
what is ectocervix?
squamous epithelium
only bottom layer has dividing cells
153
what is endocervix?
single layer of cuboidal cells containing mucin, no visible cell division
154
what can allow virus entry in cervix?
microabrasions exposing basement membrane
155
what are koilocytes? cause?
squamous epithelium undergoing number of structural changes e.g. irregular nuclei , halo around nuclei, clear edge
caused by HPV replicating in squamous cells
156
what do low risk HPV subtypes result in and what are they repsonsible for?
free viral DNA in cell
viral warts
157
what do high risk HPV subtypes do with their DNA?
incorporate their DNA into host cell
158
what are viral E6 and E7 proteins responsible for?
reactivating cell cycle in cells not normally proliferatimg
159
what does persistent infection and disruption of cell cycle result in?
proliferation of epithelial cells without external stimulus
precursor lesions for cervical cancer
CIN, CGIN
160
what do E6/E7 do?
bind to RB which promotes cell cycle
binds to p53 disrupting cell death and prolonging life of cell
induce centrosome duplicatinon and genomic instability
upregulate telomerase preventing replicative senescence
161
what are people vaccinated for now for HPV?
2 high risk subtypes for cervical cancer risk
2 low risk subtypes for viral warts risk
162
what is CIN?
cervical intraepithelial neoplasia
CIN 1,2,3
163
what happens to most patients with CIN1? where does it affect?
resolves without treatment
bottom 3rd of squamous epithelia
164
where does CIN2 effect?
bottom and middle 3rd of squamous epithelia
165
where does CIN3 effect?
full thickness of squamous epithelia
166
what is CIN3?
precursor lesion for squamous cell carcinoma
takes more than 2 years to develop into invasive carcinoma
167
what is CGIN?
cervical glandular intraepithelial neoplasia
less common and precursor lesion for adenocarcimoma
in endocervical epithelium
168
what changes happen in cervical epithelia when patients are affected by CIN?
less glycogen in upper layers of cells
nuclei have darker appearance and less cytoplasm
koilocytosis occurs
enlarged nuclei
may see dividing cells in CIN3
169
What happens to samples from cervical screening?
All tested for HPV
If positive, cytology testing occurs
170
What happens with HPV tests in cervical screening? What happens if positive/negative?
Automated test for 14 types of HPV
Positive, negative or fail
Positive - tested for cytology
Negative - recall in 5 years
171
3 steps of thin prep process?
dispersion
cell collection
cell transfer
172
what is dyskaryosis?
in cervical cytology
cells from transformation zone are spread out
dyskaryotic cells will have enlarged, irregularly shaped nuclei
173
what is grading of dyskaryosis? what do they equate to and what then happens?
mild moderate or severe
depends on size of nucleus
roughly equates to CIN1, CIN2 or CIN3
biopsy for cconfirmation
174
what do normal endocervical cells form?
sheets with even nuclei
looks like honeycomb
175
what happens with patients that have positive HPV test but no cell changes? why? what if there are cell changes?
back in 1 year for repeat test
dont want to treat patients at low risk for cancer
referred to colcoscopy for investigation
176
what is colposcopy? what is used to highlight abnormalities? what can be done?
examination of cervix with microscope
acetic acid
biopsies, and treatments for abnormalities
177
how many women in scotland will develop breast cancer?
1 in 8
178
what happens in breast screening?
women aged 50-70 invited to attend every 3 years for mammogram to detect disease early
2 xrays taken of each breat
179
what happens if abnormal results are seen in breast screening?
seen at specialist clinic for triple assessment
- examination
- radiology (repeat mammogram/ultrasound)
- biopsy
180
what does normal breast tissue look like?
central ductal structure
multiple lobular structures around duct
majority of breast is adipose tissue
each duct has 2 layers of cells
181
why might you see a blue appearance on breast biopsies?
as cells have larger nucleus
182
how common is bowel cancer?
third most common
183
function of bowel screening?
detecting precancerous changes e.g. polyps and early cancers which are treatable
184
what is a polyp?
abnormal clumb of cells
185
who is invited to bowel screening and how often? what happens?
men and women 50-74 every 2 years
faecal immunichemical test sent in post to complete at home
tested for haemoglobin
186
why are bowel cancers tested for haemoglobin?
bowel cancer often causes bleeding
187
what level of haemoglobin means patients are refferred to colonoscopy#?
above 80ugHb/g faeces
188
what are the comopnents of a normal bowel?
regular tube like structures which produce mucin
lots of cytoplasm with mucin to lubricate GI tract
layers of mucosa and muscle
189
what can cause problems with water and electrolyte homeostasis?
haemorrhage: loss of water and electrolytes due to blood loss
unusual eating/drinking behaviour e.g. too much salt intake
severe dehydration
diarrhoeal disease e.g. cholera
unintended consequences of drug actions
190
Which diuretics can cause water and electrolyte loss unintentionally and why? How to fix this?
Lasix
Potassium depletion
Drugs should be made with potassium supplement
191
What is a diuretic?
drugs that increase urine production
192
What is normal water intake and where does this water come from?
2.5L/day
1200ml water
1000ml food e.g. water in rice
metabolic 300ml
193
What is metabolic component of water intake?
carbohydrate in food oxidised to make co2 and water
194
What is the output of water in the body and where does this come from?
2.5L a day
1500ml urine
100ml sweat
200ml faeces
700ml insensible loss
195
What is insensible loss in the body?
evaporation from skin or in respiratory gases
196
when does sweat loss increase? what happens to urine in humid conditions?
during heavy exercise in hot/humid conditions
urine decreased as body trying to conserve water
197
what is the salt limit a day?
6g
198
what is renal blood flow at rest?
625ml/100g/min
199
why does the kidney require a high blood flow?
tissue metabolism and filtration
200
what is the blood pressure in glomerular capillaries?
50-60mmHg
201
Sequence of blood vessels in kidney?
afferent arteriole
glomerular capillaries
efferent arteriole
tubular capillaries
venule
202
Why is glomerular capillary pressure high?
higher blood flow
203
How many neprons are in the kidneys?
a million
204
2 types of nephron? where is water reabsoprition more effective?
superficial - shorter
juxta-medullary - longer
juxta-medullary nephrons
205
what is nephron wall composed of?
continuous layer of epithelium
206
4 sections of nephrons?
pct
loop of henle
dct
collecting duct
207
why are there different cell shapes in nephron walls?
for different activities e.g. surface area and ion pumping
208
what are the 4 steps in kidneys?
ultrafiltration
reabsorption
secretion
expletion
209
what is ultrafiltration driven by in kidneys?
high blood pressure in glomerular capillaries
210
what is the filtration rate in kidneys?
90-140ml/min
211
what is the function of reabsopriton?
retaining substances in the body
water, glucose, amino acids, electrolytes
212
why dont we accumulate chemicals e.g. pesticides in body? downside to this?
reabosption
dont accumulate drugs so they dont last long e.g. antibiotics
213
what is the function of secretion? is it faster or slower than filtration? what examples of secreted substances?
eliminating substances
faster
amminia, uric acid, drugs, hydrogen
214
what can pumping rates in kidneys be controlled by?
hormones
215
what do glomerular capillaries interdigitate with? where?
epithelial cells
zigzag portion on outer glomerular capillary
216
how is blood fitered through glomerulus?
high glomerular capillary pressure pushes water and small molecules through slits between podocytes
217
what pressure are glomerular capillaries?
55mmHg
218
what is the cut off of KD in glomerular capillaries/
67KD
219
Why can you test for high blood pressure with haemoglovin?
high haemoglobin levels in pee could mean high blood pressure as haemoglobin is borderline between fitting through podocyte slits
higher pressure means more get through slits
220
When can filtration in glomerulus go wrong?
inflammatory kidney disease
lots of free haemoglobin can clog filters
221
function of brush border in PCT?
increases surface area
222
what happens in proximal convuluted tubule?
active reabsorption of glucose, amino acids, sodium, potassium
water reabsorption
223
what happens by the end of PCT? how much volume of filtrate is reduced?
complete reabsotpion of glucose and amino acids
substantial reabsorption of sodium and water
2/3 of filtreate
224
wall in ascent on loop of henle vs descent into medulla?
ascent: thicker, thicker towards collecting tubuke
descent - thinner
225
function of thin part of loop of henle?
passive function
226
function of thick portion of loop of henle?
pumping mechanism
recycles electrolytes
227
why is tip of loop of henle 4x more concentrated than plasma?
electrolyte collects at bottom of loop
228
what does recycling of electrolytes in LOH generate?
high degree of osmotic pressure
up to 1200mOsm
229
what is plasma osmotic pressure?
300mOsm
230
Function of distal convuluted tubule?
same job as PCT but less intense
less liquid handled here
has electrolyte and water reabsorption
no glucose transporters
231
What can happen to water present in collecting duct and why?
if passes close to tip of LOH, big osmotic pressure from loop may pull water out of colelcting duct
232
what are permeabilities of collecting ducts determined by?
anti diuretic hormone - this hormone allows more water reabsorption
233
what happens in collecting tubules if trying to conserve water in regards to ADH?
secrete ADH to decrease water leaving body
234
what happens in luminal membrane is ADH present?
pre made aquaporins inserted to allow water movement
235
how fast do ADH act? what type of hormone is it?
peptide hormone
5-15 mins
236
what is blood osmolarity?
how much electrolyte is dissolved in blood
237
what happens in the blood when water intake is restricted?
plasma osmolarity increases
more ADH is secreted by hypothalamus
ADH increases the water permeability of collecting ducts
more water reabsorbed
concentrated urine produced
238
max concentration of urine?
1200 mOsm
239
minimum urine output ?
1ml/min
240
what happens in the blood if excess urine is consumed?
plasma osmolarity falls
hypothalamus secretes less ADP
collecting duct walls lose permability to water
dilite yrine produced
241
max urine output?
20ml/min
242
half life of ADH in circulation?
15 minutes
243
What does hypofiltration initiate?
secretion of renin by juxtaglomerular apparatus
244
function of renin?
splits angiotensin to make angiotensin I which is converted to angiotensin II
245
function of angiotensin II ?
vasoconstrictor
246
function of renin/angiotensin/aldosterone system?
regulates renal blood flow
and glomerular filtration rate
247
what system enhances the angiotensin system?
sympathetic nerves
248
when does aldosterone increase? what is it secreted by?
when electrolyte concentrations fall
glomerulosa cells of adrenal cortex
249
what does aldosterone increase do?
increases reabsorption of sodium and clorine ion from loop, distal tubule and duct cells
increases potassium secretion
250
what increases at the same time as electrolyte reabsorption?
water reabsorption
251
why does aldestorone make more dilute sweat? what does it try to conserve?
reabsorbed sodium and chlorine
salt
