Anatomy and embryology of Urinary system

Question 1

What are the components of the urinary system? And what are their individual functions?

Answer 1

1. Kidneys - maintain homeostasis by blood filtration.
2. Ureter - carries urine from kidney to urinary bladder.
3. Urinary bladder - stores urine, allowing urination to be controlled.
4. Urethra - carries urine from bladder to outside body.

Question 2

Why is the urinary system important? (5 points)

Answer 2

• Removes metabolic waste from blood by filtration and excretion.
• Regulates plasma electrolytes and blood pressure.
• Help to stabilise the pH
• Reabsorption of small molecules.
• Produces erythropoietin
  (stimulant of RBC production by bone marrow).

Question 3

At what level do the kidneys lie?

Answer 3

Retroperitoneal at level of T12-L3.

Question 4

What vertebral level is the transpyloric plane and what lies at this level?

Answer 4

L1 - Hilus of kidney lies at this level.

Question 5

Each kidney is enclosed by 4 layers, what are they?

Answer 5

1. Fibrous renal capsule
2. Fatty renal capsule
3. Renal fascia - libro fatty tissue
4. Pararenal fatty tissue - mainly on posterior aspects of kidney.

Question 6

What are the posterior relations of the kidney?

Answer 6

Diaphragm
Psoas major
Quadratus lumborum
12th rib

Question 7

What are the structures that make contact with the anterior surface of the right kidney?

Answer 7

Suprarenal gland 
Liver 
Duodenum 
Colon 
Jejunum

Question 8

What are the structures that make contact with the anterior surface of the left kidney?

Answer 8

Suprarenal gland 
Stomach 
Spleen 
Pancreas 
Small intestine 
Left colonic flexure

Question 9

At what vertebral level are the paired renal arteries given off from abdominal aorta?

Answer 9

L1/L2

Question 10

What are the arteries and veins supplying the kidneys?

VAP

Answer 10

Right Renal artery (segmental branches x5)
Right Renal vein
Left renal artery (segmental branches x5)
Left renal vein

Question 11

Where do the renal veins drain into?

Answer 11

Inferior Vena Cava

Question 12

Where does the left renal vein travel?

Answer 12

Anterior to aorta, relatively long.

Question 13

Where does the right renal vein travel?

Answer 13

Directly, relatively short.

Question 14

Where does the left renal artery travel?

Answer 14

Directly, relatively short.

Question 15

Where does the right renal artery travel?

Answer 15

Posterior to IVC, relatively long.

Question 16

What is the lymphatic drainage of the kidneys?

Answer 16

Lateral aortic / para-aortic lymph nodes.

Question 17

What is the nerve supply of the kidneys?

Answer 17

Renal plexus: sympathetic T10-L1, sensory afferent = T11-12

Question 18

What are the arteries of the urinary bladder?

Answer 18

Branches of the internal iliac artery

Question 19

What are the veins of the urinary bladder?

Answer 19

Drains into the internal iliac veins

Question 20

What are the lymphatics of the urinary bladder?

Answer 20

External iliac lymph nodes: Suprapubic part.

Internal iliac lymph nodes: Infrapubic part.

Question 21

Nerve supply of the urinary bladder?

Answer 21

Sympathetic: T11-L2
Para: S2-4
Somatic: pudendal nerve (voluntary control)

Question 22

What are the constrictions of the ureter?

Answer 22

First constriction = ureter passes over inferior renal pole (abdominal part)
Second constriction = ureter crosses over external iliac vessels
Third constriction: ureter traverses the bladder wall (intramural part)
* stones may lodge here.

Question 23

What is contain in the internal structure of the kidney?

Answer 23

Cortex and medulla.
Medulla: Pyramid - Papilla - minor calyx - major calyx - pelvis - ureter.
Renal lobe.

Question 24

What is the functional unit of the kidney?

Answer 24

The Nephron - purified blood going back via renal veins.

Question 25

1. What is a nephron? 2. What is the renal corpuscles? 3. What is uriniferous tubule?

Answer 25

1. Nephron = renal corpuscles + renal tubules 2. Renal corpuscles = Glomerulus + bowmen's capsule 3. Uriniferous tubule = nephron + collecting duct

Question 26

What is the function of the proximal convoluted tubule?

Answer 26

Reabsorption.

Question 27

What is the difference in the histology of the cortex and the medulla?

Answer 27

``` Cortex = Glomerulus Medulla = all the tubes. ```

Question 28

What is significant about the histology of the ureter?

Answer 28

Star shaped lumen.

Question 29

What are the most common developmental anomalies in urinary system?

Answer 29

``` Aberrant renal arteries Pelvic kidney Unilateral double kidney Horseshoe kidney Double ureter Congenital polysistic kidney disease Pancake kidney ```

Question 30

What does the intermediate mesoderm form?

Answer 30

Urinary and reproductive systems

Question 31

What is the allantois?

Answer 31

Out pouching of endoderm at the hindgut that extends into the body stalk. Body stalk later forms umbilical cord.

Question 32

1. What is the cloaca? | 2. What is it divided into?

Answer 32

1. Single posterior opening - used to expel faces. 2. Rectum posteriorly Urogenital sinus anteriorly

Question 33

What does the urogenital sinus form?

Answer 33

Urinary bladder and caudal end forms urethra

Question 34

What forms the definitive kidney?

Answer 34

A ureteric bud that develops off the mesonephric duct. And metanephric mesoderm. Reciprocally induce each other.

Question 35

What happens to the ureteric bud?

Answer 35

Undergoes repeated branching - stalk becomes ureter, expanded cranial end becomes renal pelvis.

Question 36

How do the kidneys Ascent?

Answer 36

Initially lie on either side of bladder and in developing pelvis. Due to growth of lower body they ascend. Lie in upper abdomen (T12-L3) Ascent stops when come in contact with adrenal glands. Rotates to hilum faces medially.

Question 37

What is the bladder? | What is function of detrusor muscle?

Answer 37

Bag of smooth muscle, arranged in spiral, longitudinal and circular bundles = detrusor muscle * contraction of this muscle is mainly responsible for emptying the bladder during micturition.

Question 38

Where does the bladder lie?

Answer 38

Midline posterior to pubic bones. Lies anterior to reproductive system and rectum.

Question 39

What does the trigone of bladder contain?

Answer 39

2 vesicoureteric openings. | - 1-2cm oblique passage through muscular wall

Question 40

What is defined as being the upper urinary tract?

Answer 40

Anything above the bladder: 1. Kidneys - parenchyma, pelvi-calyceal system 2. Ureters - Pelvi-uteric junction, ureter, vesicle-uteric junction (valve allows one way traffic)

Question 41

What is defined as being the lower urinary tract?

Answer 41

1. Bladder 2. Bladder outflow tract: - bladder neck - prostate - external urethral sphincter/pelvic floor - urethra - urethral meatus - foreskin - testes