Anatomical Organisation Of The Excretory System

Question 1

Where are the kidneys in relation to the body?

Answer 1

Located on either side of the vertebral column, between vertebrae T12 and L3

Question 2

The structure of the kidney?

Answer 2

• renal capsule
• cortex
• medulla (renal pyramids)
• papilla
• nephron
• minor/major calyx
• renal pelvis
• ureter
• inferior vena cava and aorta
• renal artery/vein
  (Adrenal gland sits above the kidney)

Question 3

The structure of the nephron?

Answer 3

• arcuate artery/vein
• efferent/afferent arteriole
• peritubular capillaries
• vasa recta
• Bowman’s capsule and glomerulus
• proximal convoluted tubule
• loop of Henlé (thick ascending and thin descending limb)
• distal convoluted tubule
• collecting duct

Medulla: vasa recta, loop of Henlé, collecting duct
Cortex: everything else and part of the collecting duct

Question 4

The structure of the glomerulus?

Answer 4

3 layers made up for filtration:

• capillary endothelium, basement membrane and podocytes
• highly fenestrated allowing molecules passage
• podocytes; foot-like process which integrate forming a filter bed

Question 5

What are the main functions of the kidney?

Answer 5

Excretion is metabolic waste products
Excretion of drugs
Regulate the vol, electrolyte content and pH of extracell fluid

Question 6

What are some characteristics of the kidneys?

Answer 6

1.2L of blood flows through the kidneys each minute

Filters approx 120L per day 99% of water reab

Question 7

What is the function of the glomerulus?

Answer 7

6m^2 filtration per kidney
Highly fenestrated
Uncharged molecules such as salts, glucose and amino acids can pass through filtration

Question 8

What is the composition of the filtrate?

Answer 8

Water, ions, glucose and small proteins

Flows into the bowmans capsules and PCT

Question 9

How to determine the GFR?

Answer 9

GFR = UV/P
U: solute conc in urine
V: conc of urine excreted per min
P: solute conc in plasma
Max GFR: 125ml/Mum