Renal Physiology Lecture 1: Anatomy of the Urinary System and Kidneys

Question 1

Location/ position of the kidneys

Answer 1

• bean-shaped and located in the posterior aspect of the abdomen behind the peritoneum and positioned on either side of the spine

Question 2

location of adrenal gland

Answer 2

located above each kidney

Question 3

What supplies the kidney?

Answer 3

• renal artery
• renal vein
• lymphatics

Question 4

Where are nephrons located?

Answer 4

In each kidney → over a million nephrons each

Question 5

What is the purpose of the nephrons?

Answer 5

filter system

Each nephron includes a filter, called the glomerulus, and a tubule. The nephrons work through a two-step process: the glomerulus filters your blood, and the tubule returns needed substances to your blood and removes wastes.

Question 6

How does urine leave the kidney?

Answer 6

via ureter from each kidney which drain into bladder which then accumulates and is releases through the urethra

Question 7

urethral position in men

Answer 7

• urethra passes through the prostate gland
• Traverses through the penile shaft (same with seman)

Question 8

urethral position in females

Answer 8

• Shorter length and only for urine
• Anterior to vagina & anus

Question 9

Kidney structure

Answer 9

• Renal hilum located medially
  
  • Features renal neurovascular bundle
    
    • Arterial supply, venous drainage, lymphatics, nerves
  • Exit point of the ureter
• Renal capsule
  
  • Protective of inner structures
  • Facilitates hemodynamic function

Question 10

2 key regions of the kidneys

Answer 10

Outer cortex & Inner medulla

• Medulla features renal pyramids
  
  • End in renal papillae projecting into the renal pelvis (i.e. upper ureter)
• Papillae drain into minor calyces later joining into major calyces
• Calyces, renal pelvis & ureter contain contractile elements which serve to push urine toward the bladder

Question 11

Cardiac output received by the kidneys

Answer 11

Kidneys receive a significant proportion of cardiac output

• Receive proportion of blood flow which is about 22% cCO or 1100 mL/min.

Question 12

Renal artery progressively branches into….

Answer 12

• Interlobar arteries
• Arcuate arteries
• Interlobular arteries
• Afferent arterioles

Question 13

What do afferent arterioles give rise to?

Answer 13

Afferent arterioles give rise to glomerular capillaries

• Capillaries coalesce to form efferent arterioles that branch to form peritubular capillaries

Question 14

What do the peritubular capillaries form from?

Answer 14

Capillaries coalesce to form efferent arterioles that branch to form peritubular capillaries

Question 15

What do peritubular capillaries drain into?

Answer 15

Peritubular capillaries drain into interlobular veins which join progressively to form: arcuate veins, interlobar veins, renal vein.

Question 16

How are the kidney capillary beds arranged?

Answer 16

Kidney contains two capillary beds in series which is one of the few examples of this type of arrangement because most are arranged in parallel