CH24 P1

List the components of the urinary system and know the general functions of each.

kidney

• produce urine

ureters

• transport urine toward the urinary bladder

urinary bladder

• temporarily stores urine before urination

urethra

• conducts urine to exterior

Are the kidneys the same size?

yes

Do both kidneys sit at the same level in the body?

no, right kidney is inferior to left

Between which vertebrae will you find the kidneys?

T12-L3

What is the purpose of the hilum?

enter and exit

Be able to trace the renal circulation in the correct order.

renal a → segmental a → interlobar a → arcuate a → interlobular a → afferent arteriole → glomerulus → efferent arteriole → peritubular capillaries/vasa recta → interlobular v → arcuate v → interlobar v → renal v

What are the two main components of the nephron?

renal corpuscle and renal tubule

What are the components of the renal corpuscle?

glomerular (bowman's) capsule

glomerulus

What are the components of the renal tubule?

a. proximal convoluted tubule

b. loop of henle (nephron loop)

c. distal convoluted tubule

What type of tissue forms the PCT?

cuboidal cells with abundant microvilli

What type of tissue forms the DCT?

cuboidal cells with less microvilli

Which area of the renal tubule has a brush border?

PCT

Understand how the lumens of the DCT and PCT look different from one another.

PCT has a fuzzy lumen

DCT has a clear lumen

What layer of Bowman’s capsule forms the capsular wall?

parietal layer

What layer of Bowman’s capsule is the inner layer?

visceral layer

What are podocytes?

cells that cover the glomerulus

Where is the capsular space located?

between parietal and visceral layer

What process occurs in the glomerulus?

blood filter

What blood vessel carries blood into the glomerulus?

Afferent Arteriole

What blood vessel carries blood out of the glomerulus?

Efferent Arteriole

How are the diameters of the afferent and efferent arterioles different from each other?

afferent has a larger diameter

List the two types of cells that comprise the juxtaglomerular apparatus.

Juxtaglomerular

Extraglomerular Mesangial

What are the cells of the macula densa part of?

part of the DCT

What are the juxtaglomerular cells part of?

cells of the afferent and efferent arteriole

What does the juxtaglomerular apparatus secrete?

reenin and erythropoietin

Which type of nephron has a shorter loop of Henle?

Cortical Nephron

Which has a long loop of Henle?

Juxtamedullary Nephron

Where is the renal corpuscle for a cortical nephron located?

within the renal cortex

Where is the renal corpuscle for a juxtamedullary nephron located?

near the medulla

Know what type of vessel surrounds each type of nephron.

efferent arteriole

Which type of nephron allows for the formation of a concentrated urine?

juxtamedullary

Do collecting ducts receive fluid from more than one nephron?

yes

Collecting ducts deliver fluid to the:

renal cortex and renal medulla

To what structure will a papillary duct deliver fluid?

minor calyx

Where does glomerular filtration occur?

glomerulus

What is created during glomerular filtration?

filtrate

Know where each of the nitrogenous wastes comes from.

1. Glomerular Filtration

• from blood to capsular space

2. Tubular Reabsorption

• from tubular fluid to blood

3. Tubular Secretion

• from blood to tubular fluid in renal tube

What components should be part of the filtrate

H2O

electrolytes

amino acids

glucose

urobilin

excess hormones

nitrogenous wastes

What items should NOT be part of the filtrate?

blood cells and most proteins are not part of the filtrate

List the layers of the filtration membrane in the correct order.

1. Fenestrated Capillary Endothelium

2. Basal Lamina

3. Filtration Slits

Understand how the size of the molecules filtered changes as you move through the layers.

1. Fenestrated Capillary Endothelium

• 70-100nm

2. Basal Lamina

• 8nm

3. Filtration Slits

• 6-7nm

Which layer blocks things based on their charge?

basal lamina

Understand the secretion/reabsorption table – don’t learn any numbers, just know what numbers
mean if I give you some.

amount in filtrate > urine

• solute was reabsorbed

amount in filtrate < urine

• solute was secreted

Understand how the myogenic mechanism will respond to changes in blood pressure.

decreased BP

• vasodilate afferent arteriole widened arteriole allows more blood into glomerulus, prevents a decrease in BP in glomerulus

increased BP

• vasoconstrict afferent arteriole narrowed arteriole allows less blood into glomerulus, prevents an increase in BP in glomerulus

What structure releases renin?

juxtaglomerular apparatus

Where Is angiotensinogen released from?

liver

What does renin do?

converts angiotensinogen to angiotensin I

How is angiotensin I converted to angiotensin II?

ACE (angiotensin converting enzyme) released by the lungs

Know what effects will result from the activation of angiotensin II.

• vasoconstriction in systemic vessels

• decreased GFR -> decreases urine output

  • increases blood volume

• ADH released

  • increased thirst

  • decrease urine output

• aldosterone released

increases blood volume and BP