Anatomy

Question 1

What three things make up urinary tract?

Answer 1

Ureters, urinary bladder, and urethra

Question 2

What do you call the collecting funnel for urine in the kidney?

Answer 2

Renal pelvis

Question 3

What is the order of blood going to the kidney?

Answer 3

Aorta > Renal artery > segmental artery > interlobar artery > arcuate artery > cortical radiate artery > [afferent arteriole > glomerulus (capillaries) > efferent arteriole > peritubular capillaries and vasa recta] > cortical radiate vein > arcuate vein > interlobar vein > renal vein > inferior vena cava

Question 4

Where does the sympathetic innervation of the kidneys come from?

Parasympathetic?

Answer 4

Lesser splanchnic (T10-11) and least (T12)
Lumbar splanchnic nerves (L1-2) 

Vagus N. Provides parasympathetic

Question 5

What is a glomerulus?

3 layers of Bowman’s capsule?

Answer 5

Tuft of capillaries; they are fenestrated with truly open pores

Parietal layer - simple squamous
Visceral layer - consists of podocytes
Glomerular space - contains primary filtrate

Question 6

What is special about the visceral layer of the bowman’s capsule?

Answer 6

Forms part of the filtration barrier
Single layer of cells having pedicles (foot-like processes) that make filtration-like slits.
- These are critical in regulating size, patency, and selectivity of filtration

Question 7

What’s found in the Bowman’s capsular space?

Answer 7

Primitive urine is located here.

Question 8

The basement membrane of the glomerulus allows passage of things through the wall, how large are the things that are allowed through?

Answer 8

The cut-off line is 70 kDa. Small things such as water, ions, glucose, amino acids, and urea are allowed through.

Question 9

How much fluid goes through the kidneys every day?

Answer 9

45 gallons per day.

One quart passes through every 8 minutes.

Question 10

What is it called when there is albumin in the urine? What causes this?

Answer 10

Albuminia - indicative of damage to the glumerular basement membrane.

Question 11

What is a mesangial cell and what does it do?

Answer 11

Phagocytic cells that remove cellular debris and protein aggregates.
Can control GFR
Secrete growth factors in response to injury
Can proliferate in certain diseases

Question 12

What is the most active part of the nephron in resorption and secretion?

Answer 12

Proximal convoluted tubule.

Question 13

Describe the PCT

5 things

Answer 13

Abundant microvilli (brush border) 
Abundant mitochondria
Highly folded to increase S.A. 
Many Na+ K+ ATPase pumps
Numerous types of glucose transporters and amino acid transporters.

Question 14

What part of the loop of henle has a brush border?

What’s at the other segment?

What do they do together?

Answer 14

Thin limb segment - descending loop of henle.

Thick ascending segment - simple cuboidal epithelium with numerous microvilli but no brush border

Set up hyperosmotic gradient

Question 15

What influences the distal convuluted tubule, and how?

Answer 15

Angiotensis II influences Na+ resorption.

Question 16

What receives primitive urine from several nephrons? What is the primary function?

Then what do these things form by coming together? Then?

Answer 16

Collecting ducts receive urine.
Primary function is water reabsorption.

Runs straight through cortex into deep medulla. Several join together to form larger papillary ducts.

These finally drain into renal minor calyx.

Question 17

What is the target of both ADH and aldosterone?

Answer 17

Collecting tubules / ducts

Question 18

What are the two basic cell types of the collecting tubules / ducts?
What is the role of each?

Answer 18

Light cells (principal cells) - target of aldosterone
Dark cells (intercalated cells) - involved in H+ and bicarbonate transport

Question 19

Three types of capillary beds in the kidney.

Which ones are first?

Which ones reputake H2O & salts?

Which ones go down with the loop of henle?

Answer 19

Glomerulus - Fed by afferent and drained by efferent arterioles

Peritubular capillaries - Arise from efferent arterioles; surround convoluted tubules; lined with fenestrated endothelium (reuptake of H2O & salts)

Vasa Recta - Thin-walled vessels also arise from efferents of juxtamedullary glomeruli, descending lined with continuous endothelium but fenestrated when ascending, running alongside loop of henle.

Question 20

What is responsible for renin release? When is it released?

Answer 20

Juxtaglomerular cells - mechanosensory, secrete renin if BP is low

Question 21

Where is the macula densa and what does it do?

Answer 21

Distal end of thick ascneding LoH
Chemoreceptor that monitors salt levels
Releases renin from juxtaglomerular cells if Na is low.

Question 22

What are the three regions of the male urethra?

Answer 22

Prostatic urethra - passes through prostate gland
Membranous - through the urogenital diaphragm; homologous to that found in the female
Spongy (penile) - passes through the length of the penis; longest part encased in cylindrical erectile tissue (corpus spongiosum) in the penis to reach external urethral oriface.

Question 23

The male has three regions, but the female only has one urethral region, what is it?

What are the voluntary and involuntary parts of the female urinary tract?

Answer 23

The membranous urethra - through the urogenital diaphragm.

Internal urethral sphincter - involuntary smooth muscle that is part of the bladder wall

External urethral sphincter - voluntary skeletal muscle that inhibits urination; part of the pelvic floor

Restrict the release of urine until the pressure in urinary bladder is high enough; voluntary release is needed.