Urinal system 1

Question 1

Kidney Anatomy

Answer 1

• Surfaces – Anterior (renal artery/vein above) & posterior (ureter is above)
• Margins – Lateral (greater curvature) & medial (lesser curvature)
• Poles – Superior & inferior
o Superior pole is protected by lower ribs
o Inferior pole is protected by layers of connective tissue & fat

Question 2

Right Kidney

Answer 2

o Lower than left kidney because during development, the liver pushes it downwards
o The same side as the inferior vena cava
o Right renal artery is longer
o Related to liver, duodenum & ascending colon
▪ Note: “” = separated by peritoneal membranes

Question 3

Left Kidney

Answer 3

o Same side as the aorta Left renal artery is shorter
o Related to stomach, spleen, pancreas, jejunum* &
descending colon

Question 4

kidney cortex

Answer 4

takes up the outer 1/3 of the kidney

Question 5

kidney medulla

Answer 5

takes up the inner 2/3 of the kidney

Question 6

Kidneys – Support

Answer 6

• Renal capsule
o Innermost layer attached to surface of kidney
o Protects kidney
• Adipose capsule (Perinephric Fat)
o Protective mass of fatty tissue
o Cushioning function
• Renal fascia
o Dense irregular connective tissue
o Anchors kidney and adrenals in abdomen
• Paranephric fat
o Outside of renal capsule

Question 7

Kidney Blood Supply

Answer 7

abdominal aorta, after the superior mesentery artery,
two bilateral branches come off to give rise to the renal arteries
Because the left kidney is located closer to the aorta, the left renal artery is much shorter than the right renal artery.
However, the right kidney is closer to the inferior vena cava, so the right renal vein is shorter than the left renal vein.

Question 8

Venous Drainage kidney

Answer 8

o Nephron -> Interlobular vein (cortical radiate vein) -> Arcuate Vein -> Interlobar vein -> Renal vein
o The arcuate veins (and arteries) separate the kidney cortex from the kidney medulla
o Interlobar veins separate the lobe of the kidneys by running through them.

Question 9

Arterial Supply

Answer 9

o Renal artery -> Segmental arteries -> Lobar arteries -> interlobar arteries -> arcuate arteries -> interlobular arteries -> nephron

Question 10

Renal corpuscle

Answer 10

area where filtration occurs

o Contains the glomerulus within the bowman’s capsule

Question 11

Podocytes

Answer 11

are present and have slits between their projections so that filtration will occur
o Continuous with epithelial layer of bowman’s capsule

Question 12

Uriniferous tubule

Answer 12

nephrons + collecting duct
o One million per kidney
o Collecting ducts are present in the thousands which give the renal pyramids the striated look

Question 13

Cortical Nephrons

Answer 13

o 85% of all nephrons
o Almost entirely in cortex
o Peritubular capillaries from efferent arterioles

Question 14

Juxtamedullary Nephrons

Answer 14

o 15% of all nephrons
o At cortex-medulla interface
o Loops invade deep into medulla
o Descending limb more extensive
o Involved in forming concentrated urine
o Vasa recta = cross-bridging capillaries

Question 15

Polycystic Kidney Disease

Answer 15

• Autosomal dominant trait (i.e. genetic cause)
• Single or multiple cysts
• Important cause of renal failure

Question 16

3 points of constriction (kidney stones)

Answer 16

ureteropelvic junction
pelvic inlet
entrance to bladder

Question 17

Ureters

Answer 17

Duct draining the renal pelvis to the bladder
retroperitoneal
enters bladder at a sharp angle working as a natural valve

Question 18

Pyelography

Answer 18

intravenous or retrograde injection through urethra

visualizes calices, ureter and bladder.

Question 19

Urinary bladder

Answer 19

muscular sac to store urine

detrusor muscle under autonomic control

Question 20

Urinary bladder anatomy

Answer 20

ureter
rugae
ureteric orifices
bladder neck
trigone - void of regae

Question 21

Micturition reflex

Answer 21

1. visceral stretch afferents synapse in sacral spinal cord
2. coordination by the pontine micturition center stimulates efferent limb
3. pelvic splanchnic n. contract the detrustor
4. Lumbar sympathetic to bladder are inhibited to relax the internal urethral sphincter
5. voluntary inhibition of the pudendal n. relaxes the external urethra sphincter

Question 22

Incontinence

Answer 22

leaky bladder

urethral slings to prevent stress incontinence
attached anteriorly
wraps around bladder neck to act as another sphincter