Urinary System Introduction

Question 1

Describe the location of the kidneys.

Answer 1

Retroperitoneal, At the level of T11/12.

Question 2

Where is urine made and where is it stored.?

Answer 2

Made: Kidneys
Stored: Bladder

Question 3

How does urine leave the kidneys?

Answer 3

Via the ureter smooth muscle tube.

Question 4

How does the bladder empty?

Answer 4

Via the urethra

Question 5

Describe the passage of blood through the kidney?

Answer 5

Blood enters via the renal artery from the abdominal aorta, works through a network of capillaries and leaves via the renal vein which is then connected to the inferior vena cava.

Question 6

Give 4 functions of the kidneys.

Answer 6

1. Regulation of key substances in extracellular fluid
2. Excretion of waste products
3. Endocrine functions such as synthesis of renin, erythropoietin and prostaglandins
4. Metabolism functions such as active form of vit D and catabolism of insulin

Question 7

What is osmolality?

Answer 7

Solute per kilogram of solvent.

Question 8

What is osmolarity?

Answer 8

Number of osmoles of solute per litre.

Question 9

If the extra cellular fluid is high which was does water move?

Answer 9

Out of the cell

Question 10

What is the average output of urine per day?

Answer 10

1.5L of urine

Question 11

Describe the passage of fluid through a nephron.

Answer 11

1. Glomerulus
2. Proximal convoluted tubule (In cortex)
3. Loop of Henle (Dips in and out of medulla)
4. Distal convoluted tubule (In cortex)
5. Collecting duct (Passes through medulla to renal pelvis)

Question 12

Name the type of epithelium lining the glomerulus.

Answer 12

Stratified squamous

Question 13

Name the type of epithelium lining the PCT.

Answer 13

Simple cuboidal

Question 14

Name the type of epithelium lining the DCT.

Answer 14

Simple cuboidal

Question 15

Describe the function of the glomerulus.

Answer 15

Filters everything out of the blood.

Question 16

Describe the function of the PCT.

Answer 16

Major site of reabsorbtion via peritubular capillaries. Primarily glucose and amino acids.

Question 17

Describe the function of the moop of Henle.

Answer 17

Creates a gradient of increasing osmolarity in he medulla by counter-current multiplication which allows formation of concentrated urine if water has to be conserved.

Question 18

Describe the function of the DCT.

Answer 18

Some reabsortion takes place here. Hydrogen ions are also actively secreted.

Question 19

Describe the function of the collecting duct.

Answer 19

Reabsorbs water only.