11. Uro-Genital System (TT) Flashcards
(176 cards)
1
Q
What are the three bones of the hip and how are they joined?
A
2
Q
Aside from the hip bones, what are the other bones found in the pelvis?
A
- Sacrum
- Coccyx
3
Q
What is the acetabulum and where is it found?
A
- It is the concave cavity found in the hip bone, formed by the ilium, ischium and pubis bones.
- It is where the head of femur articulates with the hip.
4
Q
How is the pelvis attached to the axial skeleton?
A
The sacro-iliac joint joins the hip bones to the spine.
5
Q
What joint joins the sacrum to the ilium in the hip? What type of joint is this?
A
- Sacroiliac joint
- It is plane synovial, but multiple ligaments mean that it is very stable
6
Q
What joint joins the pubis bones at the anterior side of the pelvic girdle? What is the notch inferior to this called?
A
- Pubis symphysis
- This forms the pubic arch inferior to it
7
Q
What is the name for the two small bumps on the pubis bones near the pubic symphysis?
A
Pubic tubercles
8
Q
What are the two arms that join the pubis and ischium?
A
Superior and inferior pubic rami
9
Q
What is the name for the two wing-like parts of the ilium bones?
A
Ala
10
Q
What is the inner surface of the ilium bone called?
A
Iliac fossa -> It is noramlly covered by the iliacus muscle.
11
Q
What is the name for the hole in the pelvic girdle formed by the ischium and rami of the pubis?
A
Obturator foramen
12
Q
What are the pelvic inlet and outlet, and what bones border each? [IMPORTANT]
A
- Pelvic inlet
- This is the superior opening to the pelvis
- Formed by the pubic symphysis anteriorly, and the pectineal line of the pubis, the arcuate line of the ilium, and the sacral promontory
- Pelvic outlet
- This is the inferior opening to the pelvis
- Formed by the inferior margin of the pubic symphysis anteriorly, and the ischiopubic ramus, the ischial tuberosity, the sacrotuberous ligament, and the inferior tip of the coccyx posteriorly
13
Q
Draw a diagram to show what marks the border of the pelvic inlet.
A
14
Q
What two bones form the obturator foramen?
A
- Pubis
- Ischium
15
Q
What are the main landmarks of the pelvis? Which of these are palpable?
A
Ilium:
- Iliac crest (palpable)
- Anterior superior iliac spine (ASIS) (palpable)
- Posterior superior iliac spine (PSIS) (palpable)
- Anterior inferior iliac spine (AIIS)
- Greater sciatic notch
Ischium:
- Ischial spine
- Ischial tuberosity (palpable)
Pubis:
- Pubic tubercle (palpable)
16
Q
What are the two ligaments that stabilise the sacroiliac joint? Where do these attach?
A
- Sacrospinous -> From ischial spine to the sacrum
- Sacrotuberous -> From ischial tuberosity to the sacrum
17
Q
Describe the greater and lesser sciatic notches and foramen. What structures form these?
A
- The sacrospinous and sacrotuberous ligaments form two foramen (greater and lesser sciatic foramen)
- The points on the bone at the superior corner of each foramen are called the greater and lesser sciatic notches
18
Q
What passes through the greater and lesser sciatic formamen?
A
- Greater sciatic foramen:
- Piriformis muscle
- Pudendal vein, artery and nerve
- Lesser sciatic foramen:
- Obturator internus muscle
19
Q
What sections does the pelvic inlet divide the pelvis into?
A
- Greater pelvis (around the abdominal cavity)
- Lesser pelvis (around the pelvic cavity)
20
Q
Describe how the pelvis is angled.
A
- It is angled so that the sacrum actually forms the roof of the pelvis
- The pubic symphysis and ASIS lie in the same plane, which is tilted about 50-60 degrees forward
- This is different to how it is usually presented (with the outlet at the top and inlet at the bottom)
21
Q
Compare the shape of the pelvis in males and females.
A
- In females, the pelvic inlet is more oval shaped and wider, to allow for the passage of a baby. The pubic arch is less acute. The bones are thinner.
- In males, the sacrum is more prominent in males and protrudes into the pelvic inlet, making it more heart-shaped. The pubic arch is more acute. The bones are thicker.
22
Q
What is the pelvic floor?
A
- Pelvic floor muscles are the layer of muscles that support the pelvic organs and span the bottom of the pelvis.
- Separates the pelvic cavity above from the perineal region (including perineum).
23
Q
What forms the pelvic floor and what is the collective name for this?
A
- Sheets of muscle
- Collectively, they are called the levator ani muscles (and the coccygeus muscle)
24
Q
Where do the levator ani muscles attach?
A
They run from the inner surface of the pubis and ischium to the coccyx.
25
Describe the muscles of the pelvic floor.
26
What nerves innervate the pelvic floor?
S3 and S4
27
What structures are found along the midline of the pelvic floor?
From posterior to anterior:
* Anococcygeal raphe
* Gap where the anus and rectum pass
* Perineal body
* Genital hiatus
28
Draw all of the structures of the pelvic floor.
29
In females, what structures have to pass through the pelvic floor and where?
* Through the small gap behind the peineal body -\> Anus
* Through the genital hiatus -\> Vagina and urethra
30
What is the function of levator ani? Which muscle in particular has a notable role?
* As the name suggests, they elevate the anus in towards the body
* The pubo rectalis muscle (a.k.a. puborectal sling), passes around the anorectal junction and helps with continence
31
What is the perineum?
* The perineum is the space between the anus and scrotum in the male and between the anus and the vulva in the female.
* It is the region of the body between the pubic symphysis (pubic arch) and the coccyx (tail bone), including the perineal body and surrounding structures.
32
Describe the position of the perineum relative to the pelvic floor.
It is **inferior** to the pelvic floor.
33
What are the two main areas of the perineum?
* Urogenital triangle (anterior)
* Anal triangle (posterior)
34
What structure defines the urogenital traingle and anal triangle? Draw the structure.
* The triangular perineal membrane forms the urogenital triangle
* Everything anterior to the perineal membrane is the anal triangle
35
What is the perineal membrane and what is its importance?
It is a triangular membrane that defines the urogenital triangle (and therefore also the anal triangle posterior to it).
36
What defines the boundaries of the perineum?
37
What structures pass through the perineum in males and females?
Urogenital triangle (i.e. perineal membrane):
* Urethra
* Vagina (only in females)
Anal triangle:
* Anus
38
What is the perineal body and where is it found?
* A pyramidal fibromuscular mass in the middle line of the perineum at the junction between the urogenital triangle and the anal triangle.
* It is between the urethra and anus (in men) or between the vagina and anus (in women)
39
In which sex is the perineal body more important and why?
Females, because it can tear during childbirth.
40
What important structures attach to the perineal body? What is the importance of this?
* Levator ani muscles
* Perineal muscles and membrane
* Supporting structures of the uterus and cervix (in females)
The perineal body can tear during childbirth, which means that the support to the structures that attach to it are weakened.
41
What is the name for the entrance and exit point of the kidneys?
Hilum
42
What is the name for the part of the urethra that passes through the perineal membrane?
Membranous part of the urethra
43
Draw a diagram to show the position of the abdominal cavity, pelvic floor, pelvic cavity and perineum.
Note that behind the peritoneal cavity in the abdomen is the retroperitoneal space.
44
Describe the position of the kidneys within the abdomen.
* Hilum of the kidneys is about 5cm lateral to the midline
* The upper poles are not symmetrical:
* Left at T11
* Right at T12
45
Which kidney lies higher in the abdomen and why?
Left, because of the liver.
46
Describe the position of the kidneys in relation to the muscles in the abdomen.
The kidneys lie on the muscles of the posterior abdominal wall: Psoas, quadratus lumboram and transversus abdominis.
47
Describe the position of the kidneys in relation to the peritoneum. What is the name for this?
They are posterior to the peritoneum -\> This is called being retroperitoneal.
48
How are the kidneys protected?
* Superior parts are protected by the 11th and 12th ribs
* Kidneys are also surrounded by a layer of peri-nephric fat
49
Describe how the kidneys relate in position to the duodenum, pancreas and spleen.
* Duodenum passes on the right-hand side of the body, covering the hilum of the right kidney
* Pancreas covers hilum of the left kidney
* Spleen covers left border of the left kidney
50
Draw a diagram to show what organs cover the different parts of the kidneys.
51
Describe the structure and different layers of the kidneys, starting from the outside and going in. [IMPORTANT]
* Capsule -\> Tough, fibrous layer
* Cortex -\> Contains the nephrons
* Medulla -\> Contains the collecting ducts
* Pelvis -\> Drains the collecting ducts (via minor and major calyces) -\> This is at the hilum of the kidney
* Ureter -\> Pelvis then drains into the ureter
52
Draw an image of a specimen of the kidneys labelled.
53
Describe what can be seen in this image.
Also note: ureters extend caudally, over the psoas muscle.
54
Compare the appearance of the renal veins and arteries in vivo.
55
Which is longer: the right renal artery or left renal artery?
Right renal artery -\> Because it passes behind the IVC.
56
Describe the blood supply to the kidneys.
* The renal arteries branch as they enter the kidney into anterior and posterior branches.
* These then branch into interlobar arteries, which are “end arteries” that supply a segment of the kidneys.
* Each interlobar artery gives rise to arcuate arteries, which in turn form interlobular arteries (and give off the vasa recta), which supply the nephrons.
Note the difference between interlobar and interlobular!
57
Do interlobular arteries form anastamoses?
No, they are end arteries and do not supply other lobes of the artery.
58
Draw a diagram to show the branching of the interlobar arteries in the kidneys.
59
What is the function of the ureter?
Passes urine from the kidneys to the bladder.
60
Describe the position of the ureter in the abdomen and its path.
It is retroperitoneal (IMPORTANT):
* Emerges from the hilum of the kidney
* Passes across psoas
* Then over the common iliac artery and vein
* Enter the bladder at the posterior wall
61
What sort of movement occurs in the ureter?
* There are peristaltic movements caused by the smooth muscle.
* So urine can be seen moving in small blobs down the ureter.
62
On what side and in which direction do the ureters enter the bladder? What is the function of this?
* Posterior side of the kidney
* Enter obliquely -\> Prevents backflow of urine and increased pressure within the bladder compresses the distal ends of the ureters shut
63
What is the trigone and what structures form it?
* A flat, triangular section at the base of the bladder
* The entrances of the ureters form two edges of the triangle, while the urethra exit forms the third
64
What forms the base of the bladder? Does this part change shape as the bladder fills?
Trigone - it does not change shape as the bladder fills.
65
What are the structures on this image?
* Arrows point towards the ureters
* The triangle is the trigone of the bladder
66
What forms the majority of the bladder walls?
* Smooth detrusor muscle
* Lined by transitional epithelium
67
What type of epithelium is in the bladder?
Transitional
68
Draw the structure of the bladder.
69
What is the peritoneal covering of the bladder?
The peritoneum is thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal organs.
70
Remember to understand the difference between perineal, peritoneal and peroneal.
* Perineal -\> The perineum is the space between the anus and scrotum in the male and between the anus and the vulva in the female.
* Peritoneal -\> The peritoneum is the serous membrane forming the lining of the abdominal cavity and the organs in the abdomen.
* Peroneal -\> To do with the lateral compartment of the leg.
71
What is the peritoneal cavity? What structures are retroperitoneal?
* The peritoneal cavity is a cavity in the abdomen which is the space between the outer parietal peritoneum on the abdominal walls and the inner visceral peritoneum covering the organs -\> The organs include the stomach, liver and spleen
* The retroperitoneal space is the area behind the peritoneal cavity -\> The organs in it include the kidneys, rectum and oesophagus (and secondary retroperitoneal organs that migrate there, including the ascending and descending colon)
72
Describe the position of the bladder.
* It lies just posterior and superior to the pubic symphysis.
* It is in the pelvic cavity, above the pelvic floor.
73
Describe the shape of the the bladder as it fills.
* As it fills, it pushes up on the peritoneal lining of the abdominal cavity above it.
* The base of the bladder remains relatively unchanged.
74
Describe the blood supply to the bladder.
From the internal iliac supply via the vesicular arteries.
75
Describe the urethra in females.
* It is relatively short
* It is attached to the anterior wall of the vagina
76
What does the vagina lead up to?
The uterus.
77
What covering is found on top of the bladder and uterus?
The peritoneal covering of the abdominal cavity.
78
What are the 3 parts of the male urethra? [IMPORTANT]
* Prostatic -\> Passing through the prostate just after leaving the bladder
* Membranous -\> Passing through the perineal membrane
* Penile -\> In the penis
79
What structure is found just inferior to the bladder?
Prostate gland
80
How many sphincters are there controlling urine entry into the urethra?
2 -\> The internal and external
81
Describe the location and difference between the internal and external sphincters of the bladder. [IMPORTANT]
* Internal
* Involuntary
* Innervated by autonomic nerves
* Found superior to the prostate, just near the exit of the bladder
* External
* Voluntary
* Innervated by somatic nerves
* Found inferior to the prostate, just next to the levator ani muscles
82
How does the bladder sense the amount of urine and how does it feed this back to the body?
* Stretch receptors in bladder wall send signals to CNS via autonomic nerves.
* This results in opening of the involuntary internal sphincters.
* As adults, we can control the release of urine using the voluntary external sphincter.
83
What are the autonomic nerves that innervate the bladder sphincters?
* Sympathetic: Presacral nerves (L1 and L2)
* Parasympathetic: Pelvic parasympathetic nerves (S2, S3 and S4)
These innervate the internal sphincter.
84
What are the somatic nerves that innervate the bladder sphincters?
Pudendal nerve innervates the external sphincter.
85
Draw a table to show which abdominal structures in males and females are:
* Intraperitoneal
* Retroperitoneal
* Subperitoneal
86
Which major artery supplies the pelvis?
Interior iliac artery
87
Describe how the internal iliac artery supplies different pelvic structures in males.
* Internal iliac artery divides into an anterior and posterior divisions
* It is only the anterior that we are interested in for now
* It gives off:
* Umbilical artery -\> To bladder (via superior vesical artery)
* Obturator artery -\> To medial compartment of thigh
* Inferior vesical artery -\> To bladder, prostate and seminal vesicles
* Internal pudendal artery -\> To perineal structures (e.g. to external genitalia)
* Middle rectal artery -\> To rectum
* Inferior gluteal artery -\> To gluteal region
88
Describe how the internal iliac artery supplies different pelvic structures in females.
* Internal iliac artery divides into an anterior and posterior divisions
* It is only the anterior that we are interested in for now
* It gives off:
* Umbilical artery -\> To bladder (via superior vesical artery)
* Obturator artery -\> To medial compartment of thigh
* Uterine artery -\> To uterus
* Vaginal artery (sometimes comes off uterine artery) -\> To vagina
* Internal pudendal artery -\> To perineal structures (e.g. to external genitalia)
* Middle rectal artery -\> To rectum
* Inferior gluteal artery -\> To gluteal region
Note: Some of the arteries are quoted as coming off the posterior rather than anterior division, but this is disputable so I have listed everything as coming off the anterior branch.
89
On an X-ray, how can you tell apart a male and female pelvis?
You cannot see any of the internal organs so you must look at the shape of the bones:
* The female pelvis is larger and broader than the male pelvis, resulting in an oval inlet.
* The male pelvis is shorter and narrower, designed to carry a heavier muscular load.
90
Is this a male or female pelvis?
Female
91
Compare the appearance of the male and female pelvis in the sagittal cross-section.
92
Give the Hounsfield units for these tissues:
* Air
* Fat
* Water
* Soft tissue
* Bone
* Metal/contrast
93
What is an advantage of MRI over CT?
* It can easily acquire direct views of the body in almost any orientation, while CT scanners typically acquire images perpendicular to the long body axis
* Offers more detailed anatomy.
* Doesn't use radiation.
94
Summarise how MRI works.
95
What are the most common imaging techniques used to image the pelvis?
Non-radiation techniques tend to be used, unless in an emergency.
96
What condition is seen on this ultrasound of the kidneys?
97
What condition is seen on this CT of the pelvis?
Kidney stones
98
What structure is shown on this MRI?
Prostate
99
Describe the different zones of the prostate.
100
Label this MRI of the male pelvis.
Note: The transition zone and peripheral zone are parts of the prostate.
101
Label this MRI of the male pelvis.
102
What is this structure shown on the MRI?
Prostate
103
Label this MRI of the scrotum.
104
Label this MRI of the female pelvis.
105
Label this MRI of the femal pelvis.
Note: It is a coronal section.
106
What are two ways in which the uterus can be viewed by ultrasound?
* Transabdominal ultrasound
* Transvaginal ultrasound
107
What imaging technique is being used here? Label the image.
Hysterosalpingogram (fluoroscopy of the female pelvis) -\> It is a plain X-ray but using a contrast to view the uterus and associated structures.
108
What congenital abnormality is seen on this MRI of the female pelvis?
Uterus Didelphys -\> Where the patient has two uteruses and two cervices.
109
What condition is this?
Endometriosis -\> The presence of functioning endometrial glands and stroma-like lesions outside of the uterus.
110
How might pelvic inflammatory disease present on ultrasound and CT?
111
What are the different parts of the urinary system?
112
What are the functions of the urinary system?
It maintains body homeostasis by:
* Formation of urine
* Remove toxins and eliminates waste products
* Regulates body fluid osmolarity and electrolyte balance
* Endocrine function
* Regulates blood pressure & volume
* Erythrocyte production
* Calcium homeostasis
113
How do the kidneys regulate blood pressure and volume?
Juxtaglomerular apparatus (JGA) -\> Secretion of renin, which participates in RAAS
114
How are the kidneys involved in erythrocyte production and when does this happen?
* They produce erythropoietin by interstitial fibroblasts
* This happens in response to hypoxia
115
How are the kidneys involved in calcium homeostasis?
They are involved in hydroxylation of Vitamin D to the active form.
116
The kidney is separated into the cortex and medulla. Which is inner and which is outer?
* Inner medulla -\> "Medulla" is derived from the Latin word for pith of a fruit
* Outer cortex -\> "Cortex" is derived from the Latin word for bark
117
What structure is found around the outside of the kidney and what is it made of?
Fibrous capsule, made of:
* Collagen
* Smooth muscle
* Elastic fibres
118
Describe the path of urine out of a kidney.
Urine flows from:
* Pyramids in the medulla
* Through calyces
* Through renal pelvis
* Into ureter
119
Give the volumes per minute for these variables:
* Blood flow through kidneys
* Flow into glomeruli
* Flow into urinary space
* Fraction reabsorbed
* Rate of urine production
* Blood flow through kidneys -\> 1.2-1.3 L/min
* Flow into glomeruli -\> About 675 ml/min
* Flow into urinary space -\> 125 ml/min
* Fraction reabsorbed -\> 99%
* Rate of urine production -\> About 1 ml/min (but varies depending on water content)
120
What is the range in the rate of urine production depending on urine production?
0.3-20 ml/min
121
What is the functional unit of a kidney?
Uriniferous tubule
122
What are the two main parts of the uriniferous tubule?
* Nephron and nephric tubule
* Collecting duct
123
What are the two types of nephron and how common is each? [EXTRA]
* Cortical (85%)
* Juxtamedullary (15%)
124
What is the tissue type of uriniferous tubules and how are they separated from the surrounding connective tissue?
* Epithelial
* Separated from connective tissue (stroma) by basal lamina
* Most of the connective tissue is occupied by rich vascular supply
125
What structure does each nephron begin with?
Renal corpuscle
126
Describe the structure of a renal corpuscle.
127
What is another name for the Bowman's capsule and glomerulus together?
Malpighian body
128
What is a renal corpuscle?
Bowman's capsule + Glomerulus = Renal corpuscle
129
What is the glomerulus supplied and drained by?
* Supplied by afferent arteriole
* Drained by efferent arteriole
130
What is the glomerulus composed of?
Anastomosing fenestrated capillaries
131
What are the two poles of a renal corpuscle and what enters/leaves at each?
* Vascular pole -\> Arterioles enter/leave here
* Urinary pole -\> Proximal convoluted tubule (PCT) leaves here
132
What are the two layers of the Bowman's capsule and what is each made of? What is the space between them called?
* Parietal (external) layer -\> Simple squamous epithelium
* Visceral (internal) layer that envelopes capillaries -\> Highly specialised cells called podocytes (foot like)
Between these layers is the Bowman's space.
133
What are podocytes?
Cells in the Bowman's capsule in the kidneys that wrap around capillaries of the glomerulus. Podocyte cells make up the epithelial lining of Bowman's capsule, the third layer through which filtration of blood takes place.
134
What are mesangial cells?
Specialised smooth muscle cells that regulate blood flow through capillaries in the glomerulus. They are interwoven with the capilarries in the conenctive tissue.
135
What are the different types of mesangial cells and what do they respond to?
* Extraglomerular
* On the vascular pole of the nephron
* Respond to signals from the macula densa and JGA
* Intraglomerular
* Situated within the renal corpuscle
* Respond to vasoactive hormones and are involved in synthesis of NO involved in intracelullar signalling
136
How are mesangial cells related to pericytes?
Mesangial cells are a type of pericyte.
137
Aside from capillary endothelial cells, name two other cells that are found within the glomerulus.
* Podocytes -\> Modified epithelial cells that wrap around capillaries of the glomerulus.
* Mesangial cels -\> Modified smooth muscle cells that are interwoven with the glomerulus
Together they support the structure and function of the glomerulus (i.e. in filtration).
138
What creates the pressure gradient required for glomerular filtration?
The afferent arteriole is wider than the efferent arteriole.
139
What are the 3 layers of the filtration apparatus involved in glomerular filtration?
1. Fenestrated capillary
2. Basal lamina
3. Podocyte slit pores
140
What type of capillary endothelium is in the glomerulus?
Fenestrated
141
What is the size of the pores in the fenestrated capillaries of the glomerulus?
70-90nm
142
What are the 3 layers of the basal lamina in the glomerular filter?
* Lamina rara interna
* Lamina densa (Type IV collagen)
* Lamina rara externa (Heparin sulphate)
143
The basal lamina is the second layer of the glomerular filter. What are two important components that allow selective filtration?
* Collagen -\> Allows filtration by size
* Heparin sulfate -\> Allows filtration by size (it is negative, so only positive are allowed through)
144
Descibe how podocytes form the third layer of the glomerular filter.
* Adjacent podocytes interdigitate to cover the basal lamina
* Each podocyte has:
* Primary processes -\> Long tentacle-like cytoplasmic extensions
* Secondary processes (a.k.a. pedicels) -\> Completely envelope most of the capillaries
* The gaps between the pedicels are called filtration slits
* Nephrins (negatively-charged) between pedicels form slit pores that are a selective filter
145
How are pedicels of podocytes attached to the underlying basement membrane?
Pedicels are held to laminin of basement membrane by integrins attached to α-actinin & talin.
146
What charge on a molecule slows its filtration through the glomerular filter and why?
Negative charge, because it is repelled by:
* Negative basement membrane (GAGs)
* Negative nephrins between podocytes
147
What are the parts of the nephron responsible for reabsorption?
148
Describe the epithelium type in the proximal tubule and how does this relate to function.
Cuboidal epithelium -\> Very leaky
149
Describe the epithelium type in the loop of Henle and how does this relate to function.
Squamous epithelium -\> Have aquaporins for movement of water
150
Describe the epithelium type in the distal tubule and how does this relate to function.
Cuboidal epithelium, EXCEPT in the macula densa where cells are tall and thin.
151
What are some structural specialisations of epithelial cells in the proximal tubule?
* Microvilli and canaliculi -\> These form a brush border that is suitable for reabsorption
* Long mitochondria provide ATP for active ion transport
* Abundant lysosomes for endocytosis and breakdown of small proteins
152
What are vasa recta and what is their function?
* Branche of the glomerular artery that surround the loop of Henle
* Essential role in generation of hypertonic interstitium by counter-current exchange
153
Compare the ascending and descending branches of the vasa recta.
* Continuous endothelial cells in descending vessels
* Fenestrated endothelial cells on ascending vessels
154
What are the three parts of the distal convoluted tubule?
* Pars recta -\> Thick loop of Henle
* Macula densa
* Pars convuluta
155
What is the easiest way of telling apart proximal and distal tubule cells in histology?
In the DCT, the cells are shorter and have no brush border.
156
What is the juxtaglomerular apparatus?
A structure in the kidney that regulates the function of each nephron.
157
Where is the juxtaglomerular apparatus found?
Between vascular pole (where the afferent and efferent arterioles are) and the distal convoluted tubule.
158
What are the 3 parts of the juxtaglomerular apparatus?
* Macula densa
* Extraglomerular mesangial cells
* Juxtaglomerular cells
159
Describe briefly how the juxtaglomerular apparatus works.
* Macula densa of distal tubule contains cells sensitive to ionic content and water volume of fluid in DCT -\> Detect Na+, K+ and Cl- conc
* Signal by releasing prostaglandins -\> Activate extraglomerular cells
* Extraglomerular mesangial cells relay this information to juxtaglomerular cells
* Juxtaglomerular cells of afferent glomerular arteriole -\> Produce renin when macula densa detects fall in Na+, K+ or Cl- in DCT
160
Describe the appearance of macula densa cells.
Tall narrow pale cells with centrally placed nuclei.
161
Label this.
162
What 3 things does the JGA regulate?
* Regulates blood pressure
* Regulates renal blood flow
* Regulates glomerular filtration rate
163
What is the type of epithelium in the collecting duct?
Simple cuboidal
164
What are the different sections of collecting ducts?
* Cortical
* Medullary
* Papillary (ducts of Bellini)
Each level is formed by the confluence of the previous level.
165
What are the two types of cell in the cortical collecting duct and what does each do?
* Principal cells -\> Aldesterone controlled Na+ reabsorpton & K+ loss
* Intercalated cells -\> Acid base control by secreting H+ or HCO3
166
What is the epithelium type of the ureter? What is it function?
Transitional epithelium (3-5 layers thick) -\> It protects the wall against urine.
167
Describe the structure of the ureter wall.
* Mucosa
* Fibrous connective tissue
* Muscular coat (muscularis)
168
What is the epithelium type in the bladder?
Transitional epithelium
169
What are plaques in the bladder, what are they made of and what is their function?
* The plasma membranes of epithelial cells in the bladder contain thickened plaque regions
* Contain glycoprotein -\> Protect cells and is impermeable to water and salt
* The plaques hold reserve plasma membrane for when the bladder is stretched
170
Draw the positions of the sphincters of the ureter.
171
What is the name for the muscle in the bladder wall?
Detrusor muscle
172
What is the function of contraction and relaxation of the detrusor muscle?
* The detrusor muscle relaxes to allow your bladder to fill
* Contracts to squeeze out urine
173
Describe the structure of the bladder wall.
* Mucosa -\> Made of transitional epithelium and lamina propria
* Submucosa (connective tissue layer)
* Detrusor muscle
* Adventitia (connective tissue again)
174
How many layers of muscle does the detrusor muscle have? What are they?
3 layers -\> 2 layers of longitudinal muscle sandwiching a layer of circular muscle
(Note: The layers are interlaced)
175
Summarise the innervation of the pelvis, perineum and lower limbs.
* Sympathetic and parasympathetic (S2-S4) supply to the pelvic organs
* Sacral nerve somatic nerve supply to the perineum and lower limb
176
