Urinary 2

Question 1

What structures make up the the renal corpuscle? What structures feed fluid in and out of the corpuscle?

Answer 1

Structures:

Glomerulus

Bowman’s Capsule (and space)

Blood:

Blood enters through afferent arterioles

Exits via efferent arterioles

These structure exist at the ‘vascular pole’ of the corpuscle

Urine:

Ultrafiltrate runs into the PCT at the urinary pole

Question 2

What cells make up the parietal layer of Bowman’s capsule?

What is their function?

Answer 2

Simple squamous epithelium

Funnel ultrafiltrate into the PCT

Question 3

Describe the structure of the filtration barrier in the renal corpuscle

Answer 3

Barrier made up of:

Fenestrated endothelium (simple squamous)

Basement membrane (shared)

Podocytes

Question 4

Why is the renal filtration barrier a good filter?

Answer 4

Fenestrated epithelium and basement membrane allow small solutes, water and proteins to pass through and preventing RBCs from passing through

Podocytes have interdigitating pedicels that create filtration slits, allowing only water and small solutes to pass

Question 5

What is this structure?

Label the boxes

Answer 5

Renal Corpuscle

Boxes from top centre clockwise:

Mesangial matrix

Parietal epithelium of Bowman’s capsule (simple squamous)

Parietal basement membrane

Bowman’s Space

Start of PCT

Urinary Pole

Filtration barrier (Visceral layer of bowmans capsule + endothelium)

Vascular Pole

DCT w/macula densa

Question 6

Describe the microscopic appearance of the PCT

Answer 6

Simple cuboidal epithelium with pronounced brush border

Question 7

What are the sections of the Loop of Henle and how do they differ?

Answer 7

4 Sections:

Pars recta

Thin descending limb

Thin ascending limb

Thick ascending limb

Difference:

appearance/epithelial lining

Question 8

Ddscribe the microscopic appearance of the thin limb of the Loop of Henle

Answer 8

Simple squamous epithelium with no brush border

Question 9

Describe the appearance of the thick limb of the Loop of Henle

Answer 9

Simple cuboidal epithelium with no brush border

Question 10

Describe the microscopic appearance of the DCT

Answer 10

Simple cuboidal epithelium with no brush border

Larger lumen than PCT

Makes contact with its parent glomerulus

Numerous mitochondria

Question 11

Identify this section of the kidney

What structures are represented by the blue, red and green boxes?

Answer 11

Cortex

Boxes:

Green - Peritubular capillaries

Blue - DCTs

Red - PCTs

Question 12

Identify this section of the kidney

What types of structures are represented by the coloured boxes?

Answer 12

Medulla

Boxes:

Green - Thick ascending limb

Red - Collecting ducts

Blue - Thin descending/ascending limb

Question 13

This is a section of the renal medulla

Label the lines

Answer 13

From left to right:

Thick ascending limb

Vasa recta

Thin limb (ascending or descending)

Thick ascending limb

Question 14

Describe what is seen here

Answer 14

Bundles of Vasa recta interspersed between tubules in the renal medulla

Question 15

What is the function of mesiangal cells?

Answer 15

Produce the mesiangal matrix found near the vascular pole of the glomerulus

Matrix offers mechanical support, but other fuctions unknown

Question 16

What are the cell types of the juxtaglomerular apparatus and where are they found?

What are the functions of these cells?

Answer 16

Macula densa

Dark staining section of DCT adjacent to vascular pole of the glomerulus

May function as a sensor for Na+ and Cl- conc

Juxtaglomerular cells

Found in the wall of the afferent arterioles

Specialised smooth muscle cells with granules that produce and secrete renin

Lacis cells

Found just outside the glomerulus near the vascular pole and the macula densa

Function not known, associated with secretion of erythropoietin

Question 17

What is the course of urine from the end of the DCT to the renal pelvis?

Answer 17

Drain into collecting ducts

Collecting ducts merge and terminate at the renal papillae to form Ducts of Bellini

Drain into the minor calycies which merge to form major calycies which in turn merge into the pelvis

Question 18

Label the boxes

Answer 18

Black

Ducts of Bellini

Red

Minor Calyx

Blue

Collecting duct

Question 19

What does this picture show?

Label the boxes

Answer 19

Ureter

Boxes, top left anticlockwise:

Transitional urothelium

Muscularis externae (Arranged longitudinal, circular, longitudinal with only the first two layers in the proximal ureter)

Adventitia

Lamina propria (connective tissue)

Question 20

What is shown here?

Label the boxes

Answer 20

Section of Bladder wall

Boxes top then bottom:

Urothelium

Detrusor muscle (Smooth muscle arranged longitudinal, circular, longitudinal)