Renal histology

Question 1

List the functions of the kidney and urinary tract

Answer 1

Maintains water and electrolyte homeostasis
Acid-base homeostasis
Excretion of toxic metabolic products
Endocrine gland producing renin and erythropoietin

Question 2

Where do the kidneys lie with respect to the peritoneum?

Answer 2

Retroperitoneal

Question 3

What is the kidney capsule made of?

Answer 3

Dense collagen fibres

Question 4

Name the contents of the renal hilum

Answer 4

Renal artery
Renal vein
Ureter

Question 5

List the structure which come between the nephron and the bladder

Answer 5

Nephron > minor calyx > major calyx > renal pelvis > ureter > bladder

Question 6

What are the two main layers of the kidney?

Answer 6

Cortex

Medulla

Question 7

What lies within the medulla?

Answer 7

Renal/medullary pyramids with papillae

Question 8

What are the renal columns? What is there function?

Answer 8

Medullary structures that lie inbetween the renal pyramids providing anchorage and pathways for vasculature

Question 9

What are the two parts of the nephron?

Answer 9

Corpuscle

Tubules

Question 10

What is the functional unit of the kidney called?

Answer 10

Nephron

Question 11

What are the structures of the renal corpuscle?

Answer 11

Glomerulus (capillaries)
Bowman’s capsule
Afferent arteriole
Efferent arteriole

Question 12

What type of cells is Bowman’s capsule composed of?

Answer 12

Squamous epithelium

Question 13

Which two layers separate the blood from the glomerular filtrate? What are the special features of each?

Answer 13

Endothelium (fenestrated)

Podocytes (interdigitated processes form filtration slits)

Question 14

Between the layers which separate the blood from the filtrate there is an abnormally thick structure, what is it?

Answer 14

Basal lamina

Question 15

What do mesangial cells produce and what is there function?

Answer 15

Mesangium (connective tissue)

Support and removal of debris

Question 16

What are the vascular and urinary poles of the corpuscle respectively?

Answer 16

Vascular pole is at the end of the corpuscle containing the capillary
Urinary pole is at the end of the corpuscle containing the tubules

Question 17

What accumulates in bowman’s space and the tubules?

Answer 17

Urinary filtrate

Question 18

Which type of cells line the proximal convuluted tubule and which specialised feature do they possess?

Answer 18

Columnar epithelium

Microvili (brush border)

Question 19

Do the renal tubules possess many or few mitochondria?

Answer 19

Many

Question 20

Is the diameter of the loop of Henle thicker or thinner than that of the proximal/distal tubules?

Answer 20

Descending limb is thin

Ascending limb is thick

Question 21

What does the loop of Henle do and why?

Answer 21

Changes the osmotic pressure in the surrounding renal medulla to change urinary output

Question 22

Where are the proximal/distal tubules and loop of Henle in relation to the kidney layers?

Answer 22

Proximal/distal tubules - cortex

Loop of Henle - medulla

Question 23

Which two types of cells compose the loop of Henle?

Answer 23

Descending limb - squamous

Ascending limb - cuboidal

Question 24

What is the vasa recta and how is it arranged within the kidney?

Answer 24

Small blood vessels

Begin in cortex –> loop down into medulla –> ascend back into cortex

Question 25

Where are the proximal and distal convoluted tubules found with respect to the kidney layers?

Answer 25

Cortex

Question 26

Which cell composes the distal convoluted tubule? What feature do these cells lack?

Answer 26

Cuboidal epithelium | No microvilli

Question 27

Where are the collecting ducts found in relation to the layers of the kidney?

Answer 27

Cortex and medulla

Question 28

What are medullary rays?

Answer 28

Straight segments of the collecting ducts, proximal and distal tubules which run perpendicular to the surface of the kidney

Question 29

Which cells compose the collecting ducts?

Answer 29

Columnar epithelium

Question 30

Which two structures are associated with the collecting ducts in the medulla of the kidney?

Answer 30

Loop of Henle | Vasa recta

Question 31

What name is given to the most distal part of the collecting duct system?

Answer 31

Ducts of bellini/papillary ducts

Question 32

What is the juxtaglomerular apparatus?

Answer 32

Portion of the distal convoluted tubule that loops back round to pass by the vascular pole of that same nephrons corpuscle

Question 33

Name the three structures of the juxtaglomerular apparatus

Answer 33

Macula densa Juxtaglomerular cells Extraglomerular mesangial/lacis cells

Question 34

What is the function of the macula densa?

Answer 34

Senses the ionic composition of the distal convoluted tubule

Question 35

What is the function of the juxtaglomerular cells?

Answer 35

Contain and secrete renin

Question 36

What is the function of lacis cells?

Answer 36

Unkown

Question 37

Are macula densa cells found near the afferent or efferent arteriole?

Answer 37

Afferent arteriole

Question 38

What type of cells compose the conducting portions of the urinary tract?

Answer 38

Urothelium/transitional epithelium

Question 39

Describe typical urothelium

Answer 39

Stratified | Contains domed umbrella cells

Question 40

Why is the urothelium arranged the way it is?

Answer 40

Variability in cell thickness - represents different states of distension Thickened apical membrane (dome) - highly impermeable barrier

Question 41

The urothelium is surrounded by lamina densa and smooth muscle. T/F

Answer 41

False - lamina propria and smooth muscle

Question 42

What changes does the structure of the ureter undergo as it moves distally?

Answer 42

Thicker smooth muscle layer | Thinner connective tissue layer

Question 43

How does the epithelium of the female urethra change as it moves distally?

Answer 43

Transitional to stratified squamous distally

Question 44

How does the epithelium of the male urethra change as it moves distally?

Answer 44

Prostatic urethra - transitional Membranous urethra - transitional to columnar Penile urethra - columnar to stratified squamous

Question 45

Describe the histology of the prostate gland

Answer 45

Tubo-alveolar glands lined by columnar secretory epithelium | Fibromuscular stroma

Question 46

Prostatic secretions compose around half of the seminal fluid volume. T/F

Answer 46

True