L21 Anatomy of Renal System

Question 1

Which of the following is not a function of the renal system?

A) Regulate red blood cell count

B) Detoxify free radicals and some drugs

C) Conjugation of bilirubin

D) Carry out gluconeogenesis in times of starvation

E) Calcium homeostasis

Answer 1

C) Conjugation of bilirubin

The functions of the renal system:

• Filter blood plasma to remove waste
• Regulate blood volume and pressure
• Regulate electrolyte balance
• Regulate body fluid pH
• Regulate red blood cell count
• Contribute to calcium homeostasis
• Detoxify free radicals and some drugs
• Carry out gluconeogenesis in times of starvation

Question 2

Which 6 organs comprise the renal system?

Answer 2

Kidneys (left/right)

Ureters (left/right)

Urinary bladder

Urethra

Question 3

In which space do the kidneys reside?

Answer 3

Retroperitoneal

Question 4

The superior and inferior poles of the kidneys are generally found at which vertebral levels?

A) T12 and L3

B) T11 and L1

C) T12 and L2

D) T11 and L3

Answer 4

A) T12 and L3

Question 5

Which bony structures partially protect the kidneys?

Answer 5

11th and 12th ribs

Question 6

Which of the layers that surround the kidney is being described?

• Smooth and transparent
• Dense, irregular connective tissue
• Continuous with outer layer of ureter
• Trauma barrier
• Maintains shape of kidney

Answer 6

Renal Capsule

This is the most deep of the three layers. The adipose capsule is the middle layer, which the renal fascia is the most superficial.

Question 7

Which of the layers that surround the kidney is being described?

• Fatty tissue
• Trauma barrier
• Maintains position of kidney

Answer 7

Adipose capsule

This is the middle layer. The renal capsule is the most deep layer, while the renal fascia is the most superficial.

Question 8

Which of the layers that surround the kidney is being described?

• Dense, irregular connective tissue
• Anchors kidney to abdominal wall and surrounding structures

Answer 8

Renal fascia

This is the most superficial layer. The renal capsule is the most deep layer, while the adipose capsule is the middle layer.

Question 9

True or false: The renal medulla is deep to the cortex?

Answer 9

True

Question 10

Which structures make up the renal parenchyma?

Answer 10

Renal cortex and medulla make up the renal parenchyma. The remaining structures are in the renal sinus.

Question 11

What structures make up a renal lobe?

Answer 11

1 renal pyramid

The overlying area of cortex

Half of each adjacent renal column

Question 12

Which renal vessels can be considered portal vessels?

Answer 12

Efferent arterioles

Question 13

What is the benefit of having arterioles at either end of the glomerular capillary bed?

Answer 13

Glomerular capillaries need high pressure for filtration. Having afferent arterioles allows control of the pressure entering the capillary bed, while efferent arterioles can constrict to maintain the pressure in the cap. bed.

An efferent venule would not be able to control pressure.

Question 14

Describe the route taken by blood between the renal artery and the renal vein.

(There are 14 changes -
yes it’s a lot to remember, think of the mnemonic)

Answer 14

1. Renal artery
2. Segmental arteries
3. Interlobar arteries
4. Arcuate ateries
5. Interlobular arteries
6. Afferent arterioles
7. Glomerular capillaries
8. Efferent arterioles
9. Peritubular capillaries
10. Interlobular veins
11. Arcuate veins
12. Interlobar veins
13. Segmental veins
14. Renal vein

(Remember: regular sex is an intense activity giving each person involved an incredibly satisfying release)

Question 15

Each nephron is supplied by how many afferent arterioles?

Answer 15

1

Question 16

What are the two components that comprise the renal corpuscle?

Answer 16

Glomerulus

Bowman’s capsule

Question 17

Where are podocytes found?

Answer 17

Form the inner visceral layer of Bowman’s capsules, enveloping glomerular capillaries

Question 18

What structures comprise the renal tubule?

Answer 18

Proximal convoluted tubule

Loop of Henle

Distal tubule

Collecting duct

Question 19

If a nephron has a short loop of Henle and the glomerulus is found in the upper two-thirds of the cortex, what type of nephron is it?

Answer 19

Cortical Nephron

85% of nephrons are cortical.

Question 20

If a nephron has a long loop of Henle and the glomerulus is found in the lower third of the cortex, what type of nephron is it?

Answer 20

Juxtamedullary

15% of nephrons are juxtamedullary

Question 21

How does the arrangement of the proximal change across it’s length?

Answer 21

Early part (pars convoluta) is convoluted, late part (pars recta) is straight.

Question 22

What type of epithelium is found in the proximal tubule?

Answer 22

Cuboidal/columnar.

Pars convoluta contains lots of microvilli - good for reabsorption.

Pars recta contains much fewer microvilli, has a much lower rate of reabsorption.

Question 23

True or false: The descending limb of the loop of Henle is thick, while the ascending limb is thin.

Answer 23

False, the descending limb is thin and the ascending limb is thick.

Question 24

Why do the cells lining the ascending limb of the loop of Henle have a lot of mitochondria?

Answer 24

Metabolically active.

These cells contains lots of pumps that require ATP.

Question 25

The final part of the loop of Henle is adjacent to what blood vessels?

Answer 25

The afferent and (often) efferent arterioles.

This allows specialist cells (macula densa) to measure salt concentration in the distal convoluted tubule and have an effect on the arterioles in response.

Known as juxtaglomerular apparatus.

Question 26

Describe the histology of the distal convoluted tubule.

Answer 26

Early part: cuboidal, very similar to ascending limb of loop of Henle

Late part: Also cuboidal, but has two cell types:

• Principal cells (ADH, aldosterone)
• Intercalated cells (Carbonic anhydrase)

Question 27

True or false: Each nephron has its own collecting duct.

Answer 27

False.

Each collecting duct receives fluid from approx. 6 distal tubules.

Question 28

Collecting ducts pair up in the medulla to form __?__. These drain into the minor calyces.

Answer 28

Ducts of Bellini